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1

Development of microsatellite markers in Cannabis sativa for DNA typing and genetic relatedness analyses  

Microsoft Academic Search

Microsatellite markers were developed for Cannabis sativa L. (marijuana) to be used for DNA typing (genotype identification) and to measure the genetic relationships between the different plants. Twelve different oligonucleotide probes were used to screen an enriched microsatellite library of Cannabis sativa in which 49% of the clones contained microsatellite sequences. Characterization of microsatellite loci in Cannabis revealed that GA\\/CT

H. J. Alghanim; J. R. Almirall

2003-01-01

2

Pharmacology of Marihuana (Cannabis sativa)  

ERIC Educational Resources Information Center

A detailed discussion of marihuana (Cannabis sativa) providing the modes of use, history, chemistry, and physiologic properties of the drug. Cites research results relating to the pharmacologic effects of marihuana. These effects are categorized into five areas: behavioral, cardiovascular-respiratory, central nervous system, toxicity-toxicology,…

Maickel, Roger P.

1973-01-01

3

Marijuana (Cannabis) and Multiple Sclerosis  

MedlinePLUS

... marijuana for medical purposes — even in the 20 states (Alaska, Arizona, California, Colorado, Connecticut, Delaware, Hawaii, Illinois, Maine, Massachusetts, Michigan, Montana, Nevada, New Hampshire, ...

4

The draft genome and transcriptome of Cannabis sativa  

PubMed Central

Background Cannabis sativa has been cultivated throughout human history as a source of fiber, oil and food, and for its medicinal and intoxicating properties. Selective breeding has produced cannabis plants for specific uses, including high-potency marijuana strains and hemp cultivars for fiber and seed production. The molecular biology underlying cannabinoid biosynthesis and other traits of interest is largely unexplored. Results We sequenced genomic DNA and RNA from the marijuana strain Purple Kush using shortread approaches. We report a draft haploid genome sequence of 534 Mb and a transcriptome of 30,000 genes. Comparison of the transcriptome of Purple Kush with that of the hemp cultivar 'Finola' revealed that many genes encoding proteins involved in cannabinoid and precursor pathways are more highly expressed in Purple Kush than in 'Finola'. The exclusive occurrence of ?9-tetrahydrocannabinolic acid synthase in the Purple Kush transcriptome, and its replacement by cannabidiolic acid synthase in 'Finola', may explain why the psychoactive cannabinoid ?9-tetrahydrocannabinol (THC) is produced in marijuana but not in hemp. Resequencing the hemp cultivars 'Finola' and 'USO-31' showed little difference in gene copy numbers of cannabinoid pathway enzymes. However, single nucleotide variant analysis uncovered a relatively high level of variation among four cannabis types, and supported a separation of marijuana and hemp. Conclusions The availability of the Cannabis sativa genome enables the study of a multifunctional plant that occupies a unique role in human culture. Its availability will aid the development of therapeutic marijuana strains with tailored cannabinoid profiles and provide a basis for the breeding of hemp with improved agronomic characteristics. PMID:22014239

2011-01-01

5

Mineral nutrition of Cannabis sativa L  

Microsoft Academic Search

Forensic laboratories can be called to examine illicit Cannabis samples (marijuana) to identify their geographical origin. They can also be required to compare different seizures to establish whether they were drawn from the same original lot. The quantitative determination of selected organic components is one of the criteria currently used in such investigations. This study aimed at evaluating the inorganic

S. Landi

1997-01-01

6

Providing medical marijuana: the importance of cannabis clubs.  

PubMed

In 1996, shortly after the San Francisco Cannabis Club was raided and (temporarily) closed by state authorities, the authors conducted an ethnographic study by interviewing selected former members to ascertain how they had benefited from the use of medical marijuana and how they had utilized the clubs. Interviews were augmented by participant observation techniques. Respondents reported highly positive health benefits from marijuana itself, and underscored even greater benefits from the social aspects of the clubs, which they described as providing important emotional supports. As such, cannabis clubs serve as crucial support mechanisms/groups for people with a wide variety of serious illnesses and conditions. The authors concluded that of the various methods so far proposed, the cannabis clubs afford the best therapeutic setting for providing medical cannabis and for offering a healing environment composed of like-minded, sympathetic friends. PMID:9692380

Feldman, H W; Mandel, J

1998-01-01

7

Cannabidiol, a safe and non-psychotropic ingredient of the marijuana plant Cannabis sativa , is protective in a murine model of colitis  

Microsoft Academic Search

Inflammatory bowel disease affects millions of individuals; nevertheless, pharmacological treatment is disappointingly unsatisfactory.\\u000a Cannabidiol, a safe and non-psychotropic ingredient of marijuana, exerts pharmacological effects (e.g., antioxidant) and mechanisms\\u000a (e.g., inhibition of endocannabinoids enzymatic degradation) potentially beneficial for the inflamed gut. Thus, we investigated\\u000a the effect of cannabidiol in a murine model of colitis. Colitis was induced in mice by intracolonic

Francesca Borrelli; Gabriella Aviello; Barbara Romano; Pierangelo Orlando; Raffaele Capasso; Francesco Maiello; Federico Guadagno; Stefania Petrosino; Francesco Capasso; Vincenzo Di Marzo; Angelo A. Izzo

2009-01-01

8

First systematic evaluation of the potency of Cannabis sativa plants grown in Albania.  

PubMed

Cannabis products (marijuana, hashish, cannabis oil) are the most frequently abused illegal substances worldwide. Delta-9-tetrahydrocannabinol (THC) is the main psychoactive component of Cannabis sativa plant, whereas cannabidiol (CBD) and cannabinol (CBN) are other major but no psychoactive constituents. Many studies have already been carried out on these compounds and chemical research was encouraged due to the legal implications concerning the misuse of marijuana. The aim of this study was to determine THC, CBD and CBN in a significant number of cannabis samples of Albanian origin, where cannabis is the most frequently used drug of abuse, in order to evaluate and classify them according to their cannabinoid composition. A GC-MS method was used, in order to assay cannabinoid content of hemp samples harvested at different maturation degree levels during the summer months and grown in different areas of Albania. This method can also be used for the determination of plant phenotype, the evaluation of psychoactive potency and the control of material quality. The highest cannabinoid concentrations were found in the flowers of cannabis. The THC concentrations in different locations of Albania ranged from 1.07 to 12.13%. The influence of environmental conditions on cannabinoid content is discussed. The cannabinoid content of cannabis plants were used for their profiling, and it was used for their classification, according to their geographical origin. The determined concentrations justify the fact that Albania is an area where cannabis is extensively cultivated for illegal purposes. PMID:22608266

Bruci, Zana; Papoutsis, Ioannis; Athanaselis, Sotirios; Nikolaou, Panagiota; Pazari, Ermira; Spiliopoulou, Chara; Vyshka, Gentian

2012-10-10

9

Providing Medical Marijuana: The Importance of Cannabis Clubs  

Microsoft Academic Search

In 1996, shortly after the San Francisco Cannabis Club was raided and (temporarily) closed by state authorities, the authors conducted an ethnographic study by interviewing selected former members to ascenain how they had benefited from the use of medical marijuana and how they had utilized the clubs. Interviews were augmented by panicipant observation techniques. Respondents reponed highly positive health benefits

Harvey W. Feldman; Jerry Mandel

1998-01-01

10

Effect of alcohol and Cannabis sativa consumption on handwriting.  

PubMed

This study reports on the separate effect of Cannabis sativa smoking and of alcohol consumption on handwriting performance in Cannabis users and in alcoholic volunteers, respectively. Handwriting samples were obtained prior to, during, and after 1 hr of Cannabis or alcohol consumption. Handwriting was evaluated for speed, letter forms, size, slant, and alignment. Cannabis sativa smoking exerted greater effect on handwriting than did alcohol drinking. This effect was noted during Cannabis smoking and lasted for 1 hr thereafter. Changes noted in handwriting performance test, which reflect involuntary muscular movement and tremor, suggest a differential CNS depressant action of the compounds used under the experimental trials listed. The results suggest possible forensic application, i.e., the use of handwriting for the purpose of signature comparison obtained under the influence of alcohol or under Cannabis intoxication. PMID:6866197

Zaki, N N; Ibraheim, M A

1983-01-01

11

Cannabidiol, a Cannabis sativa constituent, as an antipsychotic drug  

Microsoft Academic Search

A high dose of ?9-tetrahydrocannabinol, the main Cannabis sativa (cannabis) component, induces anxiety and psychotic-like symptoms in healthy volunteers. These effects of ?9-tetrahydrocannabinol are significantly reduced by cannabidiol (CBD), a cannabis constituent which is devoid of the typical effects of the plant. This observation led us to suspect that CBD could have anxiolytic and\\/or antipsychotic actions. Studies in animal models

A. W. Zuardi; J. A. S. Crippa; J. E. C. Hallak; F. A. Moreira; F. S. Guimarães

2006-01-01

12

Comparative Proteomics of Cannabis sativa Plant Tissues  

PubMed Central

Comparative proteomics of leaves, flowers, and glands of Cannabis sativa have been used to identify specific tissue-expressed proteins. These tissues have significantly different levels of cannabinoids. Cannabinoids accumulate primarily in the glands but can also be found in flowers and leaves. Proteins extracted from glands, flowers, and leaves were separated using two-dimensional gel electrophoresis. Over 800 protein spots were reproducibly resolved in the two-dimensional gels from leaves and flowers. The patterns of the gels were different and little correlation among the proteins could be observed. Some proteins that were only expressed in flowers were chosen for identification by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and peptide mass fingerprint database searching. Flower and gland proteomes were also compared, with the finding that less then half of the proteins expressed in flowers were also expressed in glands. Some selected gland protein spots were identified: F1D9.26-unknown prot. (Arabidopsis thaliana), phospholipase D beta 1 isoform 1a (Gossypium hirsutum), and PG1 (Hordeum vulgare). Western blotting was employed to identify a polyketide synthase, an enzyme believed to be involved in cannabinoid biosynthesis, resulting in detection of a single protein. PMID:15190082

Raharjo, Tri J.; Widjaja, Ivy; Roytrakul, Sittiruk; Verpoorte, Robert

2004-01-01

13

Compulsive showering and marijuana use - the cannabis hyperemisis syndrome  

PubMed Central

Patient: Male, 26 Final Diagnosis: Marihuana addiction Symptoms: Compulsive showering • nausea • vomiting Medication: — Clinical Procedure: — Specialty: Toxicology Objective: Unexpected drug reaction Background: The use or misuse of Cannabis is well recognized in the Caribbean region. Recently, the cannabinoid hyperemesis syndrome has been described. The triad is characterized by chronic marijuana use, cyclical vomiting, and compulsive bathing. With the extensive use to marijuana as a recreational drug and also the increased use as prescription medication, a patient presenting with this symptomatology needs to be assessed appropriately and this syndrome needs to be one of the differential diagnoses. Case Report: To our knowledge, we report the first such case in the Caribbean region. Here, we report on the case of a 26-year-old Caucasian male with a 3-week history of nausea and week of epigastric pain and vomiting. The patient was known to use marijuana daily for 2 years and had similar complaints for the last 6 months. Conclusions: Because this popular recreational drug is now being used with increased frequency as a prescribed medication, it is crucial that clinicians be aware of this condition, which can present as a diagnostic dilemma. PMID:23997851

Mohammed, Fawwaz; Panchoo, Kirby; Bartholemew, Maria; Maharaj, Dale

2013-01-01

14

Physical Properties of Traditional Thai Hemp Fiber (Cannabis sativa L.)  

Microsoft Academic Search

Hemp (Cannabis sativa L.) from a traditional Thai variety was used as a source of fiber in this research. The variety has been grown for a long time by the Hmong, a hill tribe, for the purpose of textiles. Hemp was grown in Chiang Mai, in the North of Thailand. Fiber fineness, fiber strength, fiber length, and lignin content of

Thitivara Sengloung; Lily Kaveeta; Jörg Müssig

2008-01-01

15

Marijuana: current concepts(†).  

PubMed

Marijuana (cannabis) remains a controversial drug in the twenty-first century. This paper considers current research on use of Cannabis sativa and its constituents such as the cannabinoids. Topics reviewed include prevalence of cannabis (pot) use, other drugs consumed with pot, the endocannabinoid system, use of medicinal marijuana, medical adverse effects of cannabis, and psychiatric adverse effects of cannabis use. Treatment of cannabis withdrawal and dependence is difficult and remains mainly based on psychological therapy; current research on pharmacologic management of problems related to cannabis consumption is also considered. The potential role of specific cannabinoids for medical benefit will be revealed as the twenty-first century matures. However, potential dangerous adverse effects from smoking marijuana are well known and should be clearly taught to a public that is often confused by a media-driven, though false message and promise of benign pot consumption. PMID:24350211

Greydanus, Donald E; Hawver, Elizabeth K; Greydanus, Megan M; Merrick, Joav

2013-01-01

16

Identification of olivetolic acid cyclase from Cannabis sativa reveals a unique catalytic route to plant polyketides  

PubMed Central

?9-Tetrahydrocannabinol (THC) and other cannabinoids are responsible for the psychoactive and medicinal properties of Cannabis sativa L. (marijuana). The first intermediate in the cannabinoid biosynthetic pathway is proposed to be olivetolic acid (OA), an alkylresorcinolic acid that forms the polyketide nucleus of the cannabinoids. OA has been postulated to be synthesized by a type III polyketide synthase (PKS) enzyme, but so far type III PKSs from cannabis have been shown to produce catalytic byproducts instead of OA. We analyzed the transcriptome of glandular trichomes from female cannabis flowers, which are the primary site of cannabinoid biosynthesis, and searched for polyketide cyclase-like enzymes that could assist in OA cyclization. Here, we show that a type III PKS (tetraketide synthase) from cannabis trichomes requires the presence of a polyketide cyclase enzyme, olivetolic acid cyclase (OAC), which catalyzes a C2–C7 intramolecular aldol condensation with carboxylate retention to form OA. OAC is a dimeric ?+? barrel (DABB) protein that is structurally similar to polyketide cyclases from Streptomyces species. OAC transcript is present at high levels in glandular trichomes, an expression profile that parallels other cannabinoid pathway enzymes. Our identification of OAC both clarifies the cannabinoid pathway and demonstrates unexpected evolutionary parallels between polyketide biosynthesis in plants and bacteria. In addition, the widespread occurrence of DABB proteins in plants suggests that polyketide cyclases may play an overlooked role in generating plant chemical diversity. PMID:22802619

Gagne, Steve J.; Stout, Jake M.; Liu, Enwu; Boubakir, Zakia; Clark, Shawn M.; Page, Jonathan E.

2012-01-01

17

Metabolic fingerprinting of Cannabis sativa L., cannabinoids and terpenoids for chemotaxonomic and drug standardization purposes  

Microsoft Academic Search

Cannabis sativa L. is an important medicinal plant. In order to develop cannabis plant material as a medicinal product quality control and clear chemotaxonomic discrimination between varieties is a necessity. Therefore in this study 11 cannabis varieties were grown under the same environmental conditions. Chemical analysis of cannabis plant material used a gas chromatography flame ionization detection method that was

Justin Thomas Fischedick; Arno Hazekamp; Tjalling Erkelens; Young Hae Choi; Rob Verpoorte

18

Cannabidiol, a constituent of Cannabis sativa, modulates sleep in rats  

Microsoft Academic Search

?9-tetrahydrocannabinol (?9-THC) and cannabidiol (CBD) are two major constituents of Cannabis sativa. ?9-THC modulates sleep, but no clear evidence on the role of CBD is available. In order to determine the effects of CBD on sleep, it was administered intracerebroventricular (icv) in a dose of 10?g\\/5?l at the beginning of either the lights-on or the lights-off period. We found that

Eric Murillo-Rodríguez; Diana Millán-Aldaco; Marcela Palomero-Rivero; Raphael Mechoulam; René Drucker-Colín

2006-01-01

19

Reliability and validity of the Marijuana Motives Measure among young adult frequent cannabis users and associations with cannabis dependence.  

PubMed

The Marijuana Motives Measure (MMM) has so far been examined mainly in student populations, often with relatively limited involvement in cannabis use. This study evaluated the factor structure of the MMM in a demographically mixed sample of 600 young adult (18-30years) frequent (?3days per week) cannabis users in the Netherlands. Analysis confirmed a five-factor solution, denoting coping, enhancement, social, conformity and expansion motives. Additionally, the original MMM was extended with two items (boredom and habit), which formed a distinct, internally consistent sixth factor labelled routine motives. In a multivariable logistic regression analysis, coping and routine motives showed significant associations with 12-month DSM-IV cannabis dependence. The results suggest general reliability and validity of the MMM in a heterogeneous population of experienced cannabis users. PMID:25240105

Benschop, Annemieke; Liebregts, Nienke; van der Pol, Peggy; Schaap, Rick; Buisman, Renate; van Laar, Margriet; van den Brink, Wim; de Graaf, Ron; Korf, Dirk J

2015-01-01

20

Les chimiotypes du chanvre (Cannabis sativa L.) Intrt pour un programme de slection  

E-print Network

Les chimiotypes du chanvre (Cannabis sativa L.) Intérêt pour un programme de sélection Gilbert Pharmacogno- sie (Nr. M. Paris), rue J.-B.-Clément, F 92290 Châtenay-Mala6ry. R�SUM� Cannabis, Cannabinoïdes, Monoecie, Chimiotypes, Sélection. L'adaptation du chanvre (Cannabis sativa L.) à différents milieux s

Paris-Sud XI, Université de

21

Marijuana, inflammation, and CT-3 (DMH-11C): cannabis leads to new class of antiinflammatory drugs.  

PubMed

CT-3, a synthetic derivative of a metabolite of marijuana, is being tested by arthritis researchers as a possible new anti-inflammatory drug. Early studies show that CT-3 may be effective without the gastric side effects of steroids and psychoactive effects of marijuana. The processes of inflammation may be important in the pathogenesis of HIV disease. Obtaining the medical benefits without the psychoactive effects of marijuana is also important, as the high associated with cannabis use can be debilitating. The drug is currently in early pre-clinical animal testing. PMID:11365002

James, J S

1998-01-23

22

Isolation of ocular hypotensive agents from Cannabis sativa.  

PubMed

Recent work in our laboratories has shown that a hydrophilic fraction from Cannabis sativa (marihuana) has extremely potent intraocular pressure (IOP)-lowering activity as measured in albino rabbits when delivered by intravenous injection. A crude extract reduced IOP by 50-60 per cent (to the episcleral venous pressure) at dosage levels of about 500 micrograms/animal. Fractionation of this material by solvent extraction, high-performance liquid chromatography, and gel filtration chromatography has produced samples with high activity at 50 micrograms/animal. The active material has been shown to be noncannabinoid and of high molecular weight. PMID:7298874

Deutsch, H M; Green, K; Zalkow, L H

1981-01-01

23

Complete sequence of a cryptic virus from hemp (Cannabis sativa).  

PubMed

Hemp (Cannabis sativa) was found to be a useful propagation host for hop latent virus, a carlavirus. However, when virus preparations were analysed by electron microscopy, along with the expected filamentous particles, spherical particles with a diameter of around 34 nm were found. RNA from virus preparations was purified, and cDNA was prepared and cloned. Sequence information was used to search databases, and the greatest similarity was found with Primula malacoides virus 1, a putative new member of the genus Partitivirus. The full sequences of RNA 1 and RNA 2 of this new hemp cryptic virus were obtained. PMID:22075921

Ziegler, Angelika; Matoušek, Jaroslav; Steger, Gerhard; Schubert, Jörg

2012-02-01

24

Cannabidiol, a Cannabis sativa constituent, as an antipsychotic drug.  

PubMed

A high dose of delta9-tetrahydrocannabinol, the main Cannabis sativa (cannabis) component, induces anxiety and psychotic-like symptoms in healthy volunteers. These effects of delta9-tetrahydrocannabinol are significantly reduced by cannabidiol (CBD), a cannabis constituent which is devoid of the typical effects of the plant. This observation led us to suspect that CBD could have anxiolytic and/or antipsychotic actions. Studies in animal models and in healthy volunteers clearly suggest an anxiolytic-like effect of CBD. The antipsychotic-like properties of CBD have been investigated in animal models using behavioral and neurochemical techniques which suggested that CBD has a pharmacological profile similar to that of atypical antipsychotic drugs. The results of two studies on healthy volunteers using perception of binocular depth inversion and ketamine-induced psychotic symptoms supported the proposal of the antipsychotic-like properties of CBD. In addition, open case reports of schizophrenic patients treated with CBD and a preliminary report of a controlled clinical trial comparing CBD with an atypical antipsychotic drug have confirmed that this cannabinoid can be a safe and well-tolerated alternative treatment for schizophrenia. Future studies of CBD in other psychotic conditions such as bipolar disorder and comparative studies of its antipsychotic effects with those produced by clozapine in schizophrenic patients are clearly indicated. PMID:16612464

Zuardi, A W; Crippa, J A S; Hallak, J E C; Moreira, F A; Guimarães, F S

2006-04-01

25

Metabolic fingerprinting of Cannabis sativa L., cannabinoids and terpenoids for chemotaxonomic and drug standardization purposes.  

PubMed

Cannabis sativa L. is an important medicinal plant. In order to develop cannabis plant material as a medicinal product quality control and clear chemotaxonomic discrimination between varieties is a necessity. Therefore in this study 11 cannabis varieties were grown under the same environmental conditions. Chemical analysis of cannabis plant material used a gas chromatography flame ionization detection method that was validated for quantitative analysis of cannabis monoterpenoids, sesquiterpenoids, and cannabinoids. Quantitative data was analyzed using principal component analysis to determine which compounds are most important in discriminating cannabis varieties. In total 36 compounds were identified and quantified in the 11 varieties. Using principal component analysis each cannabis variety could be chemically discriminated. This methodology is useful for both chemotaxonomic discrimination of cannabis varieties and quality control of plant material. PMID:21040939

Fischedick, Justin Thomas; Hazekamp, Arno; Erkelens, Tjalling; Choi, Young Hae; Verpoorte, Rob

2010-12-01

26

Multiplication vgtative in vitro du chanvre (Cannabis sativa L.). Application la conserva-  

E-print Network

- tétrahydrocannabinol, CPG. SUMMARY In vitro propagation of hemp :application to selected clones of Cannabis sativa L. for preservation of plants. Much work has been done on the breeding of hemp for agronomic and chemical criteria

Boyer, Edmond

27

The feasibility of converting Cannabis sativa L. oil into biodiesel.  

PubMed

Cannabis sativa Linn, known as industrial hemp, was utilized for biodiesel production in this study. Oil from hemp seed was converted to biodiesel through base-catalyzed transesterification. The conversion is greater than 99.5% while the product yield is 97%. Several ASTM tests for biodiesel quality were implemented on the biodiesel product, including acid number, sulfur content, flash point, kinematic viscosity, and free and total glycerin content. In addition, the biodiesel has a low cloud point (-5 degrees C) and kinematic viscosity (3.48mm(2)/s). This may be attributed to the high content of poly-unsaturated fatty acid of hemp seed oil and its unique 3:1 ratio of linoleic to alpha-linolenic acid. PMID:20624607

Li, Si-Yu; Stuart, James D; Li, Yi; Parnas, Richard S

2010-11-01

28

Genetic individualization of Cannabis sativa by a short tandem repeat multiplex system  

Microsoft Academic Search

Cannabis sativa is the most frequently used of all illicit drugs in the United States. Cannabis has been used throughout history for its stems in the production of hemp fiber, for its seed for oil and food, and for its buds and leaves as a psychoactive drug. Short tandem repeats (STRs), were chosen as molecular markers because of their distinct

Maria Angelica Mendoza Baez

2008-01-01

29

Genetic Individualization of Cannabis sativa by a Short Tandem Repeat Multiplex System  

Microsoft Academic Search

Cannabis sativa is the most frequently used of all illicit drugs in the United States. Cannabis has been used throughout history for its stems in the production of hemp fiber, for its seed for oil and food, and for its buds and leaves as a psychoactive drug. Short tandem repeats (STRs), were chosen as molecular markers because of their distinct

Maria Angelica Mendoza Baez

2008-01-01

30

Cultivation of Cannabis sativa L. in northern Morocco  

Microsoft Academic Search

Field studies on cannabis cultivation have provided socio-economic data relating to, inter alia, production, yield and income. But only laboratory analyses of cannabis plants can provide information on their chemical composition and their levels of psychoactive constituents, thus enabling them to be classed as a drug type or a fibre type. The present study, which covers cannabis in its fresh,

H. Stambouli; A. El Bouri; M. A. Bellimam; T. Bouayoun; N. El Karni

31

Genetic individualization of Cannabis sativa by a short tandem repeat multiplex system  

Microsoft Academic Search

Cannabis sativa is the most frequently used of all illicit drugs in the USA. Cannabis has been used throughout history for its stems in the\\u000a production of hemp fiber, seed for oil and food, and buds and leaves as a psychoactive drug. Short tandem repeats (STRs) were\\u000a chosen as molecular markers owing to their distinct advantages over other genetic methods.

Maria A. Mendoza; DeEtta K. Mills; Hemant Lata; Suman Chandra; Mahmoud A. ElSohly; Jose R. Almirall

2009-01-01

32

Cannabis and Cannabinoids (PDQ)  

MedlinePLUS

Overview Cannabis , also known as marijuana , is a plant grown in many parts of the world which ... Cannabis ? Cannabis , also known as marijuana , is a plant from Central Asia that is grown in many ...

33

The inheritance of chemical phenotype in Cannabis sativa L.  

PubMed Central

Four crosses were made between inbred Cannabis sativa plants with pure cannabidiol (CBD) and pure Delta-9-tetrahydrocannabinol (THC) chemotypes. All the plants belonging to the F(1)'s were analyzed by gas chromatography for cannabinoid composition and constantly found to have a mixed CBD-THC chemotype. Ten individual F(1) plants were self-fertilized, and 10 inbred F(2) offspring were collected and analyzed. In all cases, a segregation of the three chemotypes (pure CBD, mixed CBD-THC, and pure THC) fitting a 1:2:1 proportion was observed. The CBD/THC ratio was found to be significantly progeny specific and transmitted from each F(1) to the F(2)'s derived from it. A model involving one locus, B, with two alleles, B(D) and B(T), is proposed, with the two alleles being codominant. The mixed chemotypes are interpreted as due to the genotype B(D)/B(T) at the B locus, while the pure-chemotype plants are due to homozygosity at the B locus (either B(D)/B(D) or B(T)/B(T)). It is suggested that such codominance is due to the codification by the two alleles for different isoforms of the same synthase, having different specificity for the conversion of the common precursor cannabigerol into CBD or THC, respectively. The F(2) segregating groups were used in a bulk segregant analysis of the pooled DNAs for screening RAPD primers; three chemotype-associated markers are described, one of which has been transformed in a sequence-characterized amplified region (SCAR) marker and shows tight linkage to the chemotype and codominance. PMID:12586720

de Meijer, Etienne P M; Bagatta, Manuela; Carboni, Andrea; Crucitti, Paola; Moliterni, V M Cristiana; Ranalli, Paolo; Mandolino, Giuseppe

2003-01-01

34

Sensitization and Allergy to Cannabis sativa Leaves in a Population of Tomato (Lycopersicon esculentum)Sensitized Patients  

Microsoft Academic Search

Background: Cases of allergy to Cannabis sativa have occasionally been reported, but both the allergenic profile and eventual cross-reactivity pattern remain unknown. Objective: To analyze the allergenic profile of a population of patients from Spain sensitized to C. sativa and to characterize the C. sativa leaf extract. Methods: A total of 32 subjects were enrolled in the study: group A,

Carlos Hernando de Larramendi; Jerónimo Carnés; José Luís García-Abujeta; Ana García-Endrino; Elena Muñoz-Palomino; Ángel Julio Huertas; Enrique Fernández-Caldas; Ángel Ferrer

2008-01-01

35

Industrial hemp ( Cannabis sativa L.) growing on heavy metal contaminated soil: fibre quality and phytoremediation potential  

Microsoft Academic Search

Hemp (Cannabis sativa L.) was used to examine its capability as a renewable resource to decontaminate heavy metal polluted soils. The influence of heavy metals on the fibre quality was of special interest. Determination of heavy metal content was carried out by means of atomic absorption spectroscopy (AAS). Four different parts of the plant were examined: seeds, leaves, fibres and

P. Linger; J. Müssig; H. Fischer; J. Kobert

2002-01-01

36

Capillarity of flax\\/linseed ( Linum usitatissimum L.) and fibre hemp ( Cannabis sativa L.) straw fractions  

Microsoft Academic Search

In a study of the wetting properties of the fractions of unretted and frost-retted fibre straws a method to separate fibre, fine shive, and coarse shive from fibre plants is introduced and tested on bast fibre plants (Linum usitatissimum L. and Cannabis sativa L.) The method consists of optional drying of stalks, cutting of straws, milling the straws with a

H.-R Kymäläinen; M Hautala; R Kuisma; A Pasila

2001-01-01

37

Nitrogen fertilization and sex expression affect size variability of fibre hemp ( Cannabis sativa L.)  

Microsoft Academic Search

Mechanical harvesting and industrial processing of fibre hemp (Cannabis sativa L.) require uniformity of stem length and weight. In 1991 and 1992 we carried out field experiments to investigate the effects of soil nitrogen level (80 and 200 kg ha-1N) and row width (12.5, 25 and 50 cm) on the variability of weight and height in hemp plants. The crops

H. M. G. Werf; Berg van den W

1995-01-01

38

Effects of Cannabis sativa and lysergic acid diethylamide on a visual discrimination task in pigeons  

Microsoft Academic Search

Four pigeons were trained on a visual discrimination task which required conditional responding along the independent dimensions of form and color. High doses of Cannabis sativa (marihuana) extract and lysergic acid diethylamide (LSD), which were equated on the basis of their effectiveness in suppressing responding, increased responding on a color dimension but not on a form dimension. High doses of

Ronald K. Siegel

1969-01-01

39

Predicting the chemical composition of fibre and core fraction of hemp ( Cannabis sativa L.)  

Microsoft Academic Search

Summary  Fibre formation in hemp (Cannabis sativa L.) is a dynamic process. In order to follow this process, the chemical composition of the hemp stem was studied during plant development using the acid and neutral detergent fibre and lignin methods. Additionally, near infra-red spectroscopy was carried out. To predict the chemical composition of the stem samples partial least square (PLS) analysis

Marcel A. J. Toonen; Chris Maliepaard; Theo H. Reijmers; Hilko van der Voet; H. Dick Mastebroek; Hetty C. van den Broeck; Michel J. M. Ebskamp; Waltraud Kessler; Rudolf W. Kessler

2004-01-01

40

Cultivation of Cannabis sativa L. in northern Morocco.  

PubMed

Field studies on cannabis cultivation have provided socio-economic data relating to, inter alia, production, yield and income. But only laboratory analyses of cannabis plants can provide information on their chemical composition and their levels of psychoactive constituents, thus enabling them to be classed as a drug type or a fibre type. The present study, which covers cannabis in its fresh, dried and powdered forms, drew on fresh samples, obtained on the day they were harvested or immediately after preparation; that was done in order to prevent any alteration in the A-9-tetrahydrocannabinol (THC) caused by the oxidation that takes place as the product ages. The purpose of this study is to determine the THC level in 245 specimens obtained from 30 cannabis plots in three provinces of northern Morocco: Al Hoceima and Chefchaouen, where cannabis cultivation has a long tradition, and Larache, where cannabis cultivation has started only recently. Qualitative analysis using high performance liquid chromatography with diode array detection revealed the presence of both the acid and the decarboxylated form of the main cannabinoids, cannabidiol, THC and cannabinol, and gas chromatography/mass spectrometry was used for the characterization of minor cannibinoids. Quantitative analysis using gas chromatography coupled with mass spectrometry made it possible to determine the average delta-9-THC content of cannabis in its fresh form (0.5 per cent), its dry form (2.21 per cent) and its powdered form (8.3 per cent). The results show that the traditional areas of cannabis cultivation--Al Hoceima and Chefchaouen--produce cannabis with a higher delta-9-THC content than the Larache region. In addition, the present study establishes that male plants, often considered deficient in delta-9-THC, contain levels of the same order as those recorded for female plants, both in the leaves and in the tops. PMID:21338017

Stambouli, H; El Bouri, A; Bellimam, M A; Bouayoun, T; El Karni, N

2005-01-01

41

In silicio expression analysis of PKS genes isolated from Cannabis sativa L.  

PubMed Central

Cannabinoids, flavonoids, and stilbenoids have been identified in the annual dioecious plant Cannabis sativa L. Of these, the cannabinoids are the best known group of this plant's natural products. Polyketide synthases (PKSs) are responsible for the biosynthesis of diverse secondary metabolites, including flavonoids and stilbenoids. Biosynthetically, the cannabinoids are polyketide substituted with terpenoid moiety. Using an RT-PCR homology search, PKS cDNAs were isolated from cannabis plants. The deduced amino acid sequences showed 51%-73% identity to other CHS/STS type sequences of the PKS family. Further, phylogenetic analysis revealed that these PKS cDNAs grouped with other non-chalcone-producing PKSs. Homology modeling analysis of these cannabis PKSs predicts a 3D overall fold, similar to alfalfa CHS2, with small steric differences on the residues that shape the active site of the cannabis PKSs. PMID:21637580

2010-01-01

42

Long term marijuana users seeking medical cannabis in California (2001-2007): demographics, social characteristics, patterns of cannabis and other drug use of 4117 applicants  

PubMed Central

Background Cannabis (marijuana) had been used for medicinal purposes for millennia. Cannabinoid agonists are now attracting growing interest and there is also evidence that botanical cannabis is being used as self-medication for stress and anxiety as well as adjunctive therapy by the seriously ill and by patients with terminal illnesses. California became the first state to authorize medicinal use of cannabis in 1996, and it was recently estimated that between 250,000 and 350,000 Californians may now possess the physician's recommendation required to use it medically. More limited medical use has also been approved in 12 additional states and new initiatives are being considered in others. Despite that evidence of increasing public acceptance of "medical" use, a definitional problem remains and all use for any purpose is still prohibited by federal law. Results California's 1996 initiative allowed cannabis to be recommended, not only for serious illnesses, but also "for any other illness for which marijuana provides relief," thus maximally broadening the range of allowable indications. In effect, the range of conditions now being treated with federally illegal cannabis, the modes in which it is being used, and the demographics of the population using it became potentially discoverable through the required screening of applicants. This report examines the demographic profiles and other selected characteristics of 4117 California marijuana users (62% from the Greater Bay Area) who applied for medical recommendations between late 2001 and mid 2007. Conclusion This study yielded a somewhat unexpected profile of a hitherto hidden population of users of America's most popular illegal drug. It also raises questions about some of the basic assumptions held by both proponents and opponents of current policy. PMID:17980043

O'Connell, Thomas J; Bou-Matar, Che B

2007-01-01

43

Results of molecular analysis of an archaeological hemp ( Cannabis sativa L.) DNA sample from North West China  

Microsoft Academic Search

Hemp (Cannabis sativa L.) cultivation and utilization is an ancient practice to human civilization. There are some controversies on the origin\\u000a and subsequent spread of this species. Ancient plant DNA has proven to be a powerful tool to solve phylogenetic problems.\\u000a In this study, ancient DNA was extracted from an archaeological specimen of Cannabis sativa associated with archaeological human remains

Ashutosh Mukherjee; Satyesh Chandra Roy; S. De Bera; Hong-En Jiang; Xiao Li; Cheng-Sen Li; Subir Bera

2008-01-01

44

Marijuana, absinthe and the central nervous system  

Microsoft Academic Search

THERE are striking similarities between the psychological actions of the liqueur absinthe1 and the experiences frequently reported by users of marijuana2. We have therefore compared the properties of thujone and tetrahydrocannabinol (THC), which are believed to be the active principles of Artemisia absinthium and Cannabis sativa, respectively. Both substances are terpenoid, derived from the essential oils absinthol and cannabinol, and

J. Del Castillo; M. Anderson; G. M. RUBOTTOM

1975-01-01

45

Identification of candidate genes affecting  9-tetrahydrocannabinol biosynthesis in Cannabis sativa  

Microsoft Academic Search

RNA isolated from the glands of a D9-tetrahydrocannabinolic acid (THCA)-producing strain of Cannabis sativa was used to generate a cDNA library containing over 100 000 expressed sequence tags (ESTs). Sequencing of over 2000 clones from the library resulted in the identification of over 1000 unigenes. Candidate genes for almost every step in the biochemical pathways leading from primary metabolites to

M. David Marks; Li Tian; Jonathan P. Wenger; Stephanie N. Omburo; Wilfredo Soto-Fuentes; Ji He; David R. Gang; George D. Weiblen; Richard A. Dixon

2009-01-01

46

Identification of DNA markers linked to the male sex in dioecious hemp (Cannabis sativa L.)  

Microsoft Academic Search

A 400-bp RAPD marker generated by a primer of random decamer sequence has been found associated with the male sex phenotype\\u000a in 14 dioecious cultivars and accessions of hemp (Cannabis sativa L.). The primer OPA8 generates a set of bands, most of which polymorphic among all the individual plants tested, and 1 of\\u000a which, named OPA8400, present in all male

G. Mandolino; A. Carboni; S. Forapani; V. Faeti; P. Ranalli

1999-01-01

47

Plant density and self-thinning affect yield and quality of fibre hemp ( Cannabis sativa L.)  

Microsoft Academic Search

To ascertain the reasons for the high plant mortality in fibre-hemp (Cannabis sativa L.) crops in the Netherlands changes in biomass yield, plant mortality and plant morphology were investigated in a hemp cultivar grown at initial densities of 10, 30, 90 and 270 plants m?2. At 90 plants m?2 this cultivar was compared with a high bast-fibre cultivar and a

M. Wijlhuizen; J. A. A. de Schutter

1995-01-01

48

Comparison of bast fibre yield and mechanical fibre properties of hemp ( Cannabis sativa L.) cultivars  

Microsoft Academic Search

High stem yield and high bast fibre content in stem are generally accepted as important properties for fibre hemp (Cannabis sativa L.) Quality demands for fibre used in the new non-woven products have not yet been defined. The Ukrainian monoecious fibre hemp cv. Uso 11 was compared with 13 other fibre hemp cultivars in 1995–1997 in Finland (latitude 60°49? N).

Hannele S Sankari

2000-01-01

49

Variation in vegetative growth and trichomes in Cannabis sativa L. (Marihuana) in response to enviromental pollution  

SciTech Connect

Four populations of Cannabis sativa L. (marihuana) growing in their native habitat and exposed to different levels of environmental pollution were studied for several leaf morphology and leaf trichome features. Leaf length, petiole length, length and width of central leaflet, and the number of teeth on leaf margin decreased with increase in pollution. Trichome length and trichome density values were found to be higher in populations exposed to higher levels of environmental pollution.

Sharma, G.K.; Mann, S.K.

1984-07-01

50

Heat exposure of Cannabis sativa extracts affects the pharmacokinetic and metabolic profile in healthy male subjects.  

PubMed

The most important psychoactive constituent of CANNABIS SATIVA L. is ? (9)-tetrahydrocannabinol (THC). Cannabidiol (CBD), another important constituent, is able to modulate the distinct unwanted psychotropic effect of THC. In natural plant extracts of C. SATIVA, large amounts of THC and CBD appear in the form of THCA-A (THC-acid-A) and CBDA (cannabidiolic acid), which can be transformed to THC and CBD by heating. Previous reports of medicinal use of cannabis or cannabis preparations with higher CBD/THC ratios and use in its natural, unheated form have demonstrated that pharmacological effects were often accompanied with a lower rate of adverse effects. Therefore, in the present study, the pharmacokinetics and metabolic profiles of two different C. SATIVA extracts (heated and unheated) with a CBD/THC ratio > 1 were compared to synthetic THC (dronabinol) in a double-blind, randomized, single center, three-period cross-over study involving 9 healthy male volunteers. The pharmacokinetics of the cannabinoids was highly variable. The metabolic pattern was significantly different after administration of the different forms: the heated extract showed a lower median THC plasma AUC (24 h) than the unheated extract of 2.84 vs. 6.59 pmol h/mL, respectively. The later was slightly higher than that of dronabinol (4.58 pmol h/mL). On the other hand, the median sum of the metabolites (THC, 11-OH-THC, THC-COOH, CBN) plasma AUC (24 h) was higher for the heated than for the unheated extract. The median CBD plasma AUC (24 h) was almost 2-fold higher for the unheated than for the heated extract. These results indicate that use of unheated extracts may lead to a beneficial change in metabolic pattern and possibly better tolerability. PMID:22411724

Eichler, Martin; Spinedi, Luca; Unfer-Grauwiler, Sandra; Bodmer, Michael; Surber, Christian; Luedi, Markus; Drewe, Juergen

2012-05-01

51

A Cannabis sativa STR genotype database for Australian seizures: forensic applications and limitations.  

PubMed

A genetic database was established with the aim of documenting the genetic diversity of Cannabis sativa in Australia for future utilization in forensic investigations. The database consisted of genotypes at 10 validated short tandem repeat loci for 510 plants representing drug seizures from across Australia and 57 fiber samples. A total of 106 alleles and 314 different genotypes were detected. All fiber samples exhibited unique genotypes while 55% of the drug samples shared a genotype with one or more samples. Shared genotypes were mostly found within seizures; however, some genotypes were found among seizures. Statistical analysis indicated that genotype sharing was a consequence of clonal propagation rather than a lack of genetic resolution. Thus, the finding of shared genotypes among seizures is likely due to either a common supplier, or direct links among seizures. Notwithstanding the potential intelligence information provided by genetic analysis of C. sativa, our database analysis also reveals some present limitations. PMID:19302382

Howard, Christopher; Gilmore, Simon; Robertson, James; Peakall, Rod

2009-05-01

52

Marijuana  

Microsoft Academic Search

The facts on marijuana which I shall present to you this evening comprise the results of the cooperative efforts of three laboratories-the chemical investigations at the Univer- sity of Illinois, the pharmacology at Cornell Medical College under the direction of Dr. S. Loewe, and the clinical experiments at Welfare Island Hospital under the auspices of the Mayor's Committee on Marijuana

ROGER ADAMS

53

In situ analysis of cell wall polymers associated with phloem fibre cells in stems of hemp, Cannabis sativa L  

Microsoft Academic Search

A study of stem anatomy and the sclerenchyma fibre cells associated with the phloem tissues of hemp (Cannabis sativa L.) plants is of interest for both understanding the formation of secondary cell walls and for the enhancement of fibre utility\\u000a as industrial fibres and textiles. Using a range of molecular probes for cell wall polysaccharides we have surveyed the presence

Anthony W. Blake; Susan E. Marcus; James E. Copeland; Richard S. Blackburn; J. Paul Knox

2008-01-01

54

Ovipositing butterfly (Pieris brassicae L.) distinguishes between aqueous extracts of two strains of Cannabis sativa L. and THC and CBD  

Microsoft Academic Search

The ovipositing female butterfly has proved a useful tool for separating closely related strains of various plant species. Using the large white (Pieris brassicae), we have been able to distinguish between the Turkish and Mexican strains of Cannabis sativa, and demonstrate that the butterfly is sufficiently sensitive to differentiate between purified THC (tetrahydrocannabinol) and CBD (cannabidiol) - two substances which

Miriam Rothschild; J. W. Fairbairn

1980-01-01

55

The effect of cultivar and seed density on the production and fibre content of Cannabis sativa in southern England  

Microsoft Academic Search

Interest has increased in Cannabis sativa L. due to renewed demand for natural fibres and deregulation of the crop in the UK. The UK production potential and agronomic requirements of the crop were investigated by growing the cultivars Fedora 19, Felina 34, Futura 77, Uniko B and Kompolti, with a range of maturity and genetic backgrounds, at 200 and 400

H. T. H Cromack

1998-01-01

56

Molecular Cytogenetic Characterization of the Dioecious Cannabis sativa with an XY Chromosome Sex Determination System  

PubMed Central

Hemp (Cannabis sativa L.) was karyotyped using by DAPI/C-banding staining to provide chromosome measurements, and by fluorescence in situ hybridization with probes for 45 rDNA (pTa71), 5S rDNA (pCT4.2), a subtelomeric repeat (CS-1) and the Arabidopsis telomere probes. The karyotype has 18 autosomes plus a sex chromosome pair (XX in female and XY in male plants). The autosomes are difficult to distinguish morphologically, but three pairs could be distinguished using the probes. The Y chromosome is larger than the autosomes, and carries a fully heterochromatic DAPI positive arm and CS-1 repeats only on the less intensely DAPI-stained, euchromatic arm. The X is the largest chromosome of all, and carries CS-1 subtelomeric repeats on both arms. The meiotic configuration of the sex bivalent locates a pseudoautosomal region of the Y chromosome at the end of the euchromatic CS-1-carrying arm. Our molecular cytogenetic study of the C. sativa sex chromosomes is a starting point for helping to make C. sativa a promising model to study sex chromosome evolution. PMID:24465491

Divashuk, Mikhail G.; Alexandrov, Oleg S.; Razumova, Olga V.; Kirov, Ilya V.; Karlov, Gennady I.

2014-01-01

57

Structural studies of water-soluble glycoproteins from Cannabis sativa L.  

PubMed

Two carbohydrate-protein fractions, isolated from Cannabis sativa L. by extraction with water and chromatography of DEAE-cellulose, contained arabinose, galactose, glucose, mannose, galacturonic acid, 2-acetamido-2-deoxyglucose, and 2-acetamido-2-deoxygalactose. The structure of the carbohydrate moieties was investigated by methylation analysis and Smith degradation. A high percentage of end-groups indicates a large degree of branching, glucose and galactose being the main branch-points, linked at C-3 and C6. The hexoses are also present as unbranched residues in the chain, largely as (1 leads to 3)- and (1 leads to 4)-linked units and as end-groups. Arabinofuranosyl units constitute the main part of the non-reducing end-groups, and are also present as part of the chain. The polysaccharide chains are probably linked to protein through the hydroxyl group of hydroxyproline. PMID:902274

Hillestad, A; Wold, J K; Paulsen, B S

1977-08-01

58

Hemp (Cannabis sativa L.) as an Environmentally Friendly Energyplant  

NASA Astrophysics Data System (ADS)

Hemp is suitable as a renewable energy resource. The aim of this study was to clarify local hemp's (Cannabis sativa L.) possibilities for energy use. Arsenic (As), cadmium (Cd), lead (Pb) and titanium (Ti) presence in hemp was determined using an inductively coupled plasma optical emission spectrometer Optima 2100 DV. If there were increased N fertilizer rates, there were increased hemp `P?ri?i' seeds and shive yield increases, but the oil content was reduced. Arsenic content was higher in the shives than in the stems with fibre. The ash content depends on non-organic substances which the plants absorb during the vegetation season. The lignin content depends on several factors: plant parts, and the N fertilizer rate. The unexplored factors have a great effect on the ash and lignin content. Hemp is suitable for cultivation and for bio-energy production in the agro-climatic conditions in Latvia.

Poisa, Liena; Adamovics, Aleksandrs

2010-01-01

59

Antidepressant-like and anxiolytic-like effects of cannabidiol: a chemical compound of Cannabis sativa.  

PubMed

Anxiety and depression are pathologies that affect human beings in many aspects of life, including social life, productivity and health. Cannabidiol (CBD) is a constituent non-psychotomimetic of Cannabis sativa with great psychiatric potential, including uses as an antidepressant-like and anxiolytic-like compound. The aim of this study is to review studies of animal models using CBD as an anxiolytic-like and antidepressant-like compound. Studies involving animal models, performing a variety of experiments on the above-mentioned disorders, such as the forced swimming test (FST), elevated plus maze (EPM) and Vogel conflict test (VCT), suggest that CBD exhibited an anti-anxiety and antidepressant effects in animal models discussed. Experiments with CBD demonstrated non-activation of neuroreceptors CB1 and CB2. Most of the studies demonstrated a good interaction between CBD and the 5-HT1A neuro-receptor. PMID:24923339

de Mello Schier, Alexandre R; de Oliveira Ribeiro, Natalia P; Coutinho, Danielle S; Machado, Sergio; Arias-Carrión, Oscar; Crippa, Jose A; Zuardi, Antonio W; Nardi, Antonio E; Silva, Adriana C

2014-01-01

60

MARIJUANA  

Microsoft Academic Search

Marijuana continues to garner considerable attention and is the subject of intense public debate and scientific scrutiny. It is unquestionably one of the most frequently used illicit drugs throughout the world. In Western countries, the pat- tern of use among age groups has not deviated significantly since the mid-1970s. The most prevalent use occurs in per- sons who are in

BILLY R. M ARTIN; WILLIAM L. D EWEY; VINCENZO D I M ARZO

61

Metals and organic compounds in the biosynthesis of cannabinoids: a chemometric approach to the analysis of Cannabis sativa samples.  

PubMed

Illicit production and trade of Cannabis sativa affect many societies. This drug is the most popular and easy to produce. Important information for the authorities is the production locality and the indicators of a particular production. This work is an attempt to recognise correlations between the metal content in the different parts of C. sativa L., in soils where plants were cultivated and the cannabinoids content, as a potential indicator. The organic fraction of the leaves of Cannabis plants was investigated by GC-FID analysis. In addition, the determination of Cu, Fe, Cr, Mn, Zn, Ca and Mg was realised by spectroscopic techniques (FAAS and GFAAS). In this study, numerous correlations between metal content in plants and soil, already confirmed in previous publications, were analysed applying chemometric unsupervised methods, that is, principal component analysis, factor analysis and cluster analysis, in order to highlight their role in the biosynthesis of cannabinoids. PMID:24483128

Radosavljevic-Stevanovic, Natasa; Markovic, Jelena; Agatonovic-Kustrin, Snezana; Razic, Slavica

2014-01-01

62

Failure obtain “cannabis-directed behavior” and abstinence syndrome in rats chronically treated with Cannabis sativa extracts  

Microsoft Academic Search

Experiments were performed to verify whether chronic treatment with Cannabis saliva extracts would induce dependence and\\/or abstinence symptoms in rats. In Experiment one, rats ingested cannabis extract as the only fluid for 126 days. On days 1, 43, 48, 62, 80, 92 and 119 when the animals were in abstinence from previous administration of marihuana for 0 to 96 h,

José Roberto Leite; E. A. Carlini

1974-01-01

63

Nitrogen fertilization and row width affect self-thinning and productivity of fibre hemp ( Cannabis sativa L.)  

Microsoft Academic Search

In fibre hemp (Cannabis sativa L.) a high plant density is desirable, but inter-plant competition may cause self-thinning, which reduces stem yield and quality. We investigated whether agronomic factors could reduce self-thinning in hemp. The effects of soil nitrogen level (80 and 200 kg ha?1), row width (12.5, 25 and 50 cm), type of sowing implement, and thinning method on

W. C. A. van Geel; L. J. C. van Gils; A. J. Haverkort

1995-01-01

64

Marijuana Dependence: Not Just Smoke and Mirrors  

PubMed Central

Marijuana (Cannabis sativa) is the most commonly used illicit drug worldwide as well as in the Unites States. Prolonged use of marijuana or repeated administration of its primary psychoactive constituent, ?9-tetrahydrocannabinol (THC), can lead to physical dependence in humans and laboratory animals. The changes that occur with repeated cannabis use include alterations in behavioral, physiological, and biochemical responses. A variety of withdrawal responses occur in cannabis-dependent individuals: anger, aggression, irritability, anxiety and nervousness, decreased appetite or weight loss, restlessness, and sleep difficulties with strange dreams. But the long half-life and other pharmacokinetic properties of THC result in delayed expression of withdrawal symptoms, and because of the lack of contiguity between drug cessation and withdrawal responses the latter are not readily recognized as a clinically relevant syndrome. Over the past 30 years, a substantial body of clinical and laboratory animal research has emerged supporting the assertion that chronic exposure to cannabinoids produces physical dependence and may contribute to drug maintenance in cannabis-dependent individuals. However, no medications are approved to treat cannabis dependence and withdrawal. In this review, we describe preclinical and clinical research that supports the existence of a cannabinoid withdrawal syndrome. In addition, we review research evaluating potential pharmacotherapies (e.g., THC, a variety of antidepressant drugs, and lithium) to reduce cannabis withdrawal responses and examine how expanded knowledge about the regulatory mechanisms in the endocannabinoid system may lead to promising new therapeutic targets. PMID:23382144

Ramesh, Divya; Schlosburg, Joel E.; Wiebelhaus, Jason M.; Lichtman, Aron H.

2012-01-01

65

Diversity Analysis in Cannabis sativa Based on Large-Scale Development of Expressed Sequence Tag-Derived Simple Sequence Repeat Markers  

PubMed Central

Cannabis sativa L. is an important economic plant for the production of food, fiber, oils, and intoxicants. However, lack of sufficient simple sequence repeat (SSR) markers has limited the development of cannabis genetic research. Here, large-scale development of expressed sequence tag simple sequence repeat (EST-SSR) markers was performed to obtain more informative genetic markers, and to assess genetic diversity in cannabis (Cannabis sativa L.). Based on the cannabis transcriptome, 4,577 SSRs were identified from 3,624 ESTs. From there, a total of 3,442 complementary primer pairs were designed as SSR markers. Among these markers, trinucleotide repeat motifs (50.99%) were the most abundant, followed by hexanucleotide (25.13%), dinucleotide (16.34%), tetranucloetide (3.8%), and pentanucleotide (3.74%) repeat motifs, respectively. The AAG/CTT trinucleotide repeat (17.96%) was the most abundant motif detected in the SSRs. One hundred and seventeen EST-SSR markers were randomly selected to evaluate primer quality in 24 cannabis varieties. Among these 117 markers, 108 (92.31%) were successfully amplified and 87 (74.36%) were polymorphic. Forty-five polymorphic primer pairs were selected to evaluate genetic diversity and relatedness among the 115 cannabis genotypes. The results showed that 115 varieties could be divided into 4 groups primarily based on geography: Northern China, Europe, Central China, and Southern China. Moreover, the coefficient of similarity when comparing cannabis from Northern China with the European group cannabis was higher than that when comparing with cannabis from the other two groups, owing to a similar climate. This study outlines the first large-scale development of SSR markers for cannabis. These data may serve as a foundation for the development of genetic linkage, quantitative trait loci mapping, and marker-assisted breeding of cannabis. PMID:25329551

Cheng, Chaohua; Tang, Qing; Chen, Ping; Wang, Changbiao; Zang, Gonggu; Zhao, Lining

2014-01-01

66

Identity Formation, Marijuana and "The Self": A Study of Cannabis Normalization among University Students  

PubMed Central

Over the past half-century, as use of marijuana has become more widespread in Canadian society, there are indications of a normalizing process in societal reactions and experiences of use. Among other research avenues, these trends suggest a need for further exploration of young people’s understandings of how they make the choice to use or not and how decisions relate to presentation of the self. This study draws on interviews with 30 undergraduates recruited from a larger online survey of respondents at the University of Guelph, ON, Canada. In probing their perceptions of the use of marijuana, we often found that trying/using “pot” was the default option, whereas choosing not to use required more conscious effort. With specific reference to Goffman’s contribution to a situated understanding of the self, our findings are interpreted with emphasis on further theoretical development of the normalization thesis and on the role of marijuana in identity formation among persons in the process of transition to adulthood. PMID:24348431

Mostaghim, Amir; Hathaway, Andrew D.

2013-01-01

67

In planta imaging of ?9-tetrahydrocannabinolic acid in Cannabis sativa L. with hyperspectral coherent anti-Stokes Raman scattering microscopy  

NASA Astrophysics Data System (ADS)

Nature has developed many pathways to produce medicinal products of extraordinary potency and specificity with significantly higher efficiencies than current synthetic methods can achieve. Identification of these mechanisms and their precise locations within plants could substantially increase the yield of a number of natural pharmaceutics. We report label-free imaging of ?9-tetrahydrocannabinolic acid (THCa) in Cannabis sativa L. using coherent anti-Stokes Raman scattering microscopy. In line with previous observations we find high concentrations of THCa in pistillate flowering bodies and relatively low amounts within flowering bracts. Surprisingly, we find differences in the local morphologies of the THCa-containing bodies: organelles within bracts are large, diffuse, and spheroidal, whereas in pistillate flowers they are generally compact, dense, and have heterogeneous structures. We have also identified two distinct vibrational signatures associated with THCa, both in pure crystalline form and within Cannabis plants; at present the exact natures of these spectra remain an open question.

Garbacik, Erik T.; Korai, Roza P.; Frater, Eric H.; Korterik, Jeroen P.; Otto, Cees; Offerhaus, Herman L.

2013-04-01

68

Identification and quantification of cannabinoids in Cannabis sativa L. plants by high performance liquid chromatography-mass spectrometry.  

PubMed

High performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) has been successfully applied to cannabis plant extracts in order to identify cannabinoid compounds after their quantitative isolation by means of supercritical fluid extraction (SFE). MS conditions were optimized by means of a central composite design (CCD) approach, and the analysis method was fully validated. Six major cannabinoids [tetrahydrocannabinolic acid (THCA), tetrahydrocannabinol (THC), cannabidiol (CBD), tetrahydrocannabivarin (THCV), cannabigerol (CBG), and cannabinol (CBN)] were quantified (RSD < 10%), and seven more cannabinoids were identified and verified by means of a liquid chromatograph coupled to a quadrupole-time-of-flight (Q-ToF) detector. Finally, based on the distribution of the analyzed cannabinoids in 30 Cannabis sativa L. plant varieties and the principal component analysis (PCA) of the resulting data, a clear difference was observed between outdoor and indoor grown plants, which was attributed to a higher concentration of THC, CBN, and CBD in outdoor grown plants. PMID:25338935

Aizpurua-Olaizola, Oier; Omar, Jone; Navarro, Patricia; Olivares, Maitane; Etxebarria, Nestor; Usobiaga, Aresatz

2014-11-01

69

[Toxic effects of essential oil of Cannabis sativa L. and main constituents on planarian (Dugesia tigrina) (author's transl)].  

PubMed

Regenerating pieces of planarian worms are able to absorbe insoluble substances deposited on the base of the vessels in which they are cultivated. This biological test was used to study the toxic effects of the essential oil of Cannabis sativa L. The hydrocarbons such as pinene (alpha and beta), caryophyllene and so on were not toxic. On the contrary caryophyllene oxide was highly toxic. It was not possible to detect any protection by 5-hydroxytryptamine as it was the case against delta 1-tétrahydro-cannabinol and cannabidiol. PMID:754350

Fournier, G; Lenicque, P M; Paris, M R

1978-11-01

70

Marijuana. Specialized Information Service.  

ERIC Educational Resources Information Center

The document presents a collection of articles about marijuana. Article 1 reports on the results of a study by the National Academy of Sciences on the health effects of marijuana. A summary report of adverse health and behavioral consequences of cannabis (marijuana) use is provided in article 2. Article 3 presents the Surgeon General's warnings on…

Do It Now Foundation, Phoenix, AZ.

71

Effect of Ruta graveolens and Cannabis sativa alcoholic extract on spermatogenesis in the adult wistar male rats  

PubMed Central

Objective: The present study was undertaken to evaluate the effects of alcohol extracts of Ruta graveolens and Cannabis sativa that were used traditionally in medieval Persian medicine as male contraceptive drugs, on spermatogenesis in the adult male rats. Materials and Methods: Ethanol extracts of these plants were obtained by the maceration method. The male rats were injected intraperitionaly with C. sativa and R. graveolens 5% ethanol extracts at dose of 20 mg/day for 20 consecutive days, respectively. Twenty-four hours after the last treatment, testicular function was assessed by epididymal sperm count. Result: The statistical results showed that the ethanol extracts of these plants reduced the number of sperms significantly (P=0.00) in the treatment groups in comparison to the control group. The results also showed that the group, treated by extract of R. graveolens reduced spermatogenesis more than the group treated by extracts of C. sativa. Conclusion: The present study demonstrated the spermatogenesis reducing properties of the ethanol extracts of R. graveolens and C. sativa in the adult male wistar rats but more studies are necessary to reveal the mechanism of action that is involved in spermatogenesis. PMID:19718326

Sailani, M. R.; Moeini, H.

2007-01-01

72

Differential expression of genes involved in C 1 metabolism and lignin biosynthesis in wooden core and bast tissues of fibre hemp ( Cannabis sativa L.)  

Microsoft Academic Search

Plants are the major source of fibres for, e.g., textile and paper applications. Fibre hemp (Cannabis sativa L.) can be grown under a wide variety of agro-ecological conditions, is resistant to weeds and pests and, in general, drought tolerant. Fibre length and content of cellulose and lignin are important quality parameters for raw material used in cordage, textile, paper, and

Hetty C. van den Broeck; Chris Maliepaard; Michel J. M. Ebskamp; Marcel A. J. Toonen; Andries J. Koops

2008-01-01

73

Influence of agronomic factors on yield and quality of hemp ( Cannabis sativa L.) fibre and implication for an innovative production system  

Microsoft Academic Search

Research and development of an innovative production system for hemp (Cannabis sativa L.) fibre for textile use requires the integration of multidisciplinary knowledge from cultivation technique to realization of end products. Research was carried out to study the effect of the agronomic factors cultivation year (2003–2004), genotype (Futura 75 and Tiborszallasi), plant population (120, 240 and 360plantsm?2) and harvesting time

Stefano Amaducci; Alessandro Zatta; Federica Pelatti; Gianpietro Venturi

2008-01-01

74

Effects of ultraviolet-B radiation on the growth, physiology and cannabinoid production of Cannabis sativa L  

SciTech Connect

The concentration of cannabinoids in Cannabis sativa L. is correlated with high ultraviolet-B (UV-B) radiation environments. ..delta../sup 9/-Tetrahydrocannabinolic acid and cannabidiolic acid, both major secondary products of C. sativa, absorb UV-B radiation and may function as solar screens. The object of this study was to test the effects of UV-B radiation on the physiology and cannabinoid production of C. sativa. Drug and fiber-type C. sativa were irradiated with three levels of UV-B radiation for 40 days in greenhouse experiments. Physiological measurements on leaf tissues were made by infra-red gas analysis. Drug and fiber-type control plants had similar CO/sub 2/ assimilation rates from 26 to 32/sup 0/C. Drug-type control plant had higher dark respiration rates and stomatal conductances than fiber-type control plants. The concentration of ..delta../sup 9/-THC, but not of other cannabinoids) in both vegetative and reproductive tissues increased with UV-B dose in drug-type plants. None of the cannabinoids in fiber-type plants were affected by UV-B radiation. The increased level of ..delta../sup 9/-THC found in leaves after irradiation may account for the physiological and morphological insensitivity to UV-B radiation in the drug-type plants. However, fiber plants showed no comparable change in the level of cannabidoil (CBD). Resin stripped form fresh fiber-type floral tissue by sonication was spotted on filter paper and irradiated continuously for 7 days. Cannabidiol (CBD) gradually decreased when irradiated but ..delta../sup 9/-THC and cannabichromene did not.

Lydon, J.

1986-01-01

75

Analysis of cannabinoids in laser-microdissected trichomes of medicinal Cannabis sativa using LCMS and cryogenic NMR.  

PubMed

Trichomes, especially the capitate-stalked glandular hairs, are well known as the main sites of cannabinoid and essential oil production of Cannabis sativa. In this study the distribution and density of various types of Cannabis sativa L. trichomes, have been investigated by scanning electron microscopy (SEM). Furthermore, glandular trichomes were isolated over the flowering period (8 weeks) by laser microdissection (LMD) and the cannabinoid profile analyzed by LCMS. Cannabinoids were detected in extracts of 25-143 collected cells of capitate-sessile and capitate stalked trichomes and separately in the gland (head) and the stem of the latter. ?(9)-Tetrahydrocannabinolic acid [THCA (1)], cannabidiolic acid [CBDA (2)], and cannabigerolic acid [CBGA (3)] were identified as most-abundant compounds in all analyzed samples while their decarboxylated derivatives, ?(9)-tetrahydrocannabinol [THC (4)], cannabidiol [CBD (5)], and cannabigerol [CBG (6)], co-detected in all samples, were present at significantly lower levels. Cannabichromene [CBC (8)] along with cannabinol (CBN (9)) were identified as minor compounds only in the samples of intact capitate-stalked trichomes and their heads harvested from 8-week old plants. Cryogenic nuclear magnetic resonance spectroscopy (NMR) was used to confirm the occurrence of major cannabinoids, THCA (1) and CBDA (2), in capitate-stalked and capitate-sessile trichomes. Cryogenic NMR enabled the additional identification of cannabichromenic acid [CBCA (7)] in the dissected trichomes, which was not possible by LCMS as standard was not available. The hereby documented detection of metabolites in the stems of capitate-stalked trichomes indicates a complex biosynthesis and localization over the trichome cells forming the glandular secretion unit. PMID:23280038

Happyana, Nizar; Agnolet, Sara; Muntendam, Remco; Van Dam, Annie; Schneider, Bernd; Kayser, Oliver

2013-03-01

76

Investigations into the hypothesis of transgenic cannabis.  

PubMed

The unusual concentration of cannabinoids recently found in marijuana samples submitted to the forensic laboratory for chemical analysis prompted an investigation into whether genetic modifications have been made to the DNA of Cannabis sativa L. to increase its potency. Traditional methods for the detection of genetically modified organisms (GMO) were used to analyze herbal cannabis preparations. Our analyses support the hypothesis that marijuana samples submitted to forensic laboratories and characterized by an abnormal level of ?(9)-THC are the product of breeding selection rather than of transgenic modifications. Further, this research has shown a risk of false positive results associated with the poor quality of the seized samples and probably due to the contamination by other transgenic vegetable products. On the other hand, based on these data, a conclusive distinction between the hypothesis of GMO plant contamination and the other of genetic modification of cannabis cannot be made requiring further studies on comparative chemical and genetic analyses to find out an explanation for the recently detected increased potency of cannabis. PMID:22211569

Cascini, Fidelia

2012-05-01

77

Beneficial effects of a Cannabis sativa extract treatment on diabetes-induced neuropathy and oxidative stress.  

PubMed

Neuropathy is the most common complication of diabetes and it is still considered to be relatively refractory to most of the analgesics. The aim of the present study was to explore the antinociceptive effect of a controlled cannabis extract (eCBD) in attenuating diabetic neuropathic pain. Repeated treatment with cannabis extract significantly relieved mechanical allodynia and restored the physiological thermal pain perception in streptozotocin (STZ)-induced diabetic rats without affecting hyperglycemia. In addition, the results showed that eCBD increased the reduced glutathione (GSH) content in the liver leading to a restoration of the defence mechanism and significantly decreased the liver lipid peroxidation suggesting that eCBD provides protection against oxidative damage in STZ-induced diabetes that also strongly contributes to the development of neuropathy. Finally, the nerve growth factor content in the sciatic nerve of diabetic rats was restored to normal following the repeated treatment with eCBD, suggesting that the extract was able to prevent the nerve damage caused by the reduced support of this neurotrophin. These findings highlighted the beneficial effects of cannabis extract treatment in attenuating diabetic neuropathic pain, possibly through a strong antioxidant activity and a specific action upon nerve growth factor. PMID:19441010

Comelli, Francesca; Bettoni, Isabella; Colleoni, Mariapia; Giagnoni, Gabriella; Costa, Barbara

2009-12-01

78

Medical use of cannabis. Cannabidiol: a new light for schizophrenia?  

PubMed

The medical properties of cannabis have been known for many centuries; its first documented use dates back to 2800 BC when it was described for its hallucinogenic and pain-relieving properties. In the first half of the twentieth century, a number of pharmaceutical companies marked cannabis for indications such as asthma and pain, but since then its use has sharply declined, mainly due to its unpredictable effects, but also for socio-political issues. Recently, great attention has been directed to the medical properties of phytocannabinoids present in the cannabis plant alongside the main constituent ??-Tetrahydrocannabinol (THC); these include cannabinoids such as cannabidiol (CBD), cannabigerol (CBG), and tetrahydrocannabivarin (THCV). Evidence suggests an association between cannabis and schizophrenia: schizophrenics show a higher use of marijuana as compared to the healthy population. Additionally, the use of marijuana can trigger psychotic episodes in schizophrenic patients, and this has been ascribed to THC. Given the need to reduce the side effects of marketed antipsychotics, and their weak efficacy on some schizophrenic symptoms, cannabinoids have been suggested as a possible alternative treatment for schizophrenia. CBD, a non-psychoactive constituent of the Cannabis sativa plant, has been receiving growing attention for its anti-psychotic-like properties. Evidence suggests that CBD can ameliorate positive and negative symptoms of schizophrenia. Behavioural and neurochemical models suggest that CBD has a pharmacological profile similar to that of atypical anti-psychotic drugs and a clinical trial reported that this cannabinoid is a well-tolerated alternative treatment for schizophrenia. PMID:23109356

Deiana, Serena

2013-01-01

79

Cannabis as an Alternative Medicine  

Microsoft Academic Search

Cannabis - or marijuana - is one of the oldest substances known to human kind and, until quite recently, was also one of the most widely used and best understood. For millennia it was a mainstay of mainstream medicine. Only in the 20th-Century was cannabis pushed to the margins of respectability and demonized. But cannabis has made a comeback and

CRAIG JONES

80

The case for medical marijuana in epilepsy.  

PubMed

Charlotte, a little girl with SCN1A-confirmed Dravet syndrome, was recently featured in a special that aired on CNN. Through exhaustive personal research and assistance from a Colorado-based medical marijuana group (Realm of Caring), Charlotte's mother started adjunctive therapy with a high concentration cannabidiol/?(9) -tetrahydrocannabinol (CBD:THC) strain of cannabis, now known as Charlotte's Web. This extract, slowly titrated over weeks and given in conjunction with her existing antiepileptic drug regimen, reduced Charlotte's seizure frequency from nearly 50 convulsive seizures per day to now 2-3 nocturnal convulsions per month. This effect has persisted for the last 20 months, and Charlotte has been successfully weaned from her other antiepileptic drugs. We briefly review some of the history, preclinical and clinical data, and controversies surrounding the use of medical marijuana for the treatment of epilepsy, and make a case that the desire to isolate and treat with pharmaceutical grade compounds from cannabis (specifically CBD) may be inferior to therapy with whole plant extracts. Much more needs to be learned about the mechanisms of antiepileptic activity of the phytocannabinoids and other constituents of Cannabis sativa. PMID:24854149

Maa, Edward; Figi, Paige

2014-06-01

81

Medical marijuana: the conflict between scientific evidence and political ideology. Part two of two.  

PubMed

In Part I of this article, I examined the role of the Food and Drug Administration (FDA) in drug approval and then detailed the known risks of medical marijuana (any form of Cannabis sativa used--usually by smoking--to treat a wide variety of pathologic states and diseases). Part II of the article will begin by reviewing the benefits of Cannabis sativa as documented by well designed scientific studies that have been published in the peer-reviewed literature. I will then propose that ability of scientists to conduct impartial studies designed to answer the question of marijuana's role in medical therapy has been greatly hampered by political considerations. I will posit that in spite of the considerable efforts of policymakers, it is becoming apparent that marijuana's benefits should be weighed against its well-described risks. I will conclude that political advocacy is a poor substitute for dispassionate analysis and that neither popular votes nor congressional "findings" should be permitted to trump scientific evidence in deciding whether or not marijuana is an appropriate pharmaceutical agent to use in modern medical practice. Whether or not marijuana is accepted as a legitimate medical therapy should remain in the hands of the usual drug-approval process and that the statutory role of the Food and Drug Administration should be dispositive. PMID:19492213

Cohen, Peter J

2009-01-01

82

Antihyperalgesic effect of a Cannabis sativa extract in a rat model of neuropathic pain: mechanisms involved.  

PubMed

This study aimed to give a rationale for the employment of phytocannabinoid formulations to treat neuropathic pain. It was found that a controlled cannabis extract, containing multiple cannabinoids, in a defined ratio, and other non-cannabinoid fractions (terpenes and flavonoids) provided better antinociceptive efficacy than the single cannabinoid given alone, when tested in a rat model of neuropathic pain. The results also demonstrated that such an antihyperalgesic effect did not involve the cannabinoid CB1 and CB2 receptors, whereas it was mediated by vanilloid receptors TRPV1. The non-psychoactive compound, cannabidiol, is the only component present at a high level in the extract able to bind to this receptor: thus cannabidiol was the drug responsible for the antinociceptive behaviour observed. In addition, the results showed that after chronic oral treatment with cannabis extract the hepatic total content of cytochrome P450 was strongly inhibited as well as the intestinal P-glycoprotein activity. It is suggested that the inhibition of hepatic metabolism determined an increased bioavailability of cannabidiol resulting in a greater effect. However, in the light of the well known antioxidant and antiinflammatory properties of terpenes and flavonoids which could significantly contribute to the therapeutic effects, it cannot be excluded that the synergism observed might be achieved also in the absence of the cytochrome P450 inhibition. PMID:18618522

Comelli, Francesca; Giagnoni, Gabriella; Bettoni, Isabella; Colleoni, Mariapia; Costa, Barbara

2008-08-01

83

In situ analysis of cell wall polymers associated with phloem fibre cells in stems of hemp, Cannabis sativa L.  

PubMed

A study of stem anatomy and the sclerenchyma fibre cells associated with the phloem tissues of hemp (Cannabis sativa L.) plants is of interest for both understanding the formation of secondary cell walls and for the enhancement of fibre utility as industrial fibres and textiles. Using a range of molecular probes for cell wall polysaccharides we have surveyed the presence of cell wall components in stems of hemp in conjunction with an anatomical survey of stem and phloem fibre development. The only polysaccharide detected to occur abundantly throughout the secondary cell walls of phloem fibres was cellulose. Pectic homogalacturonan epitopes were detected in the primary cell walls/intercellular matrices between the phloem fibres although these epitopes were present at a lower level than in the surrounding parenchyma cell walls. Arabinogalactan-protein glycan epitopes displayed a diversity of occurrence in relation to fibre development and the JIM14 epitope was specific to fibre cells, binding to the inner surface of secondary cell walls, throughout development. Xylan epitopes were found to be present in the fibre cells (and xylem secondary cell walls) and absent from adjacent parenchyma cell walls. Analysis of xylan occurrence in the phloem fibre cells of hemp and flax indicated that xylan epitopes were restricted to the primary cell walls of fibre cells and were not present in the secondary cell walls of these cells. PMID:18299887

Blake, Anthony W; Marcus, Susan E; Copeland, James E; Blackburn, Richard S; Knox, J Paul

2008-06-01

84

Structure and function of ?1-tetrahydrocannabinolic acid (THCA) synthase, the enzyme controlling the psychoactivity of Cannabis sativa.  

PubMed

?1-Tetrahydrocannabinolic acid (THCA) synthase catalyzes the oxidative cyclization of cannabigerolic acid (CBGA) into THCA, the precursor of the primary psychoactive agent ?1-tetrahydrocannabinol in Cannabis sativa. The enzyme was overproduced in insect cells, purified, and crystallized in order to investigate the structure-function relationship of THCA synthase, and the tertiary structure was determined to 2.75Å resolution by X-ray crystallography (R(cryst)=19.9%). The THCA synthase enzyme is a member of the p-cresol methyl-hydroxylase superfamily, and the tertiary structure is divided into two domains (domains I and II), with a flavin adenine dinucleotide coenzyme positioned between each domain and covalently bound to His114 and Cys176 (located in domain I). The catalysis of THCA synthesis involves a hydride transfer from C3 of CBGA to N5 of flavin adenine dinucleotide and the deprotonation of O6' of CBGA. The ionized residues in the active site of THCA synthase were investigated by mutational analysis and X-ray structure. Mutational analysis indicates that the reaction does not involve the carboxyl group of Glu442 that was identified as the catalytic base in the related berberine bridge enzyme but instead involves the hydroxyl group of Tyr484. Mutations at the active-site residues His292 and Tyr417 resulted in a decrease in, but not elimination of, the enzymatic activity of THCA synthase, suggesting a key role for these residues in substrate binding and not direct catalysis. PMID:22766313

Shoyama, Yoshinari; Tamada, Taro; Kurihara, Kazuo; Takeuchi, Ayako; Taura, Futoshi; Arai, Shigeki; Blaber, Michael; Shoyama, Yukihiro; Morimoto, Satoshi; Kuroki, Ryota

2012-10-12

85

Antidepressant-like effect of delta9-tetrahydrocannabinol and other cannabinoids isolated from Cannabis sativa L.  

PubMed

The antidepressant action of cannabis as well as the interaction between antidepressants and the endocannabinoid system has been reported. This study was conducted to assess the antidepressant-like activity of Delta(9)-THC and other cannabinoids. Cannabinoids were initially evaluated in the mouse tetrad assay to determine doses that do not induce hypothermia or catalepsy. The automated mouse forced swim (FST) and tail suspension (TST) tests were used to determine antidepressant action. At doses lacking hypothermic and cataleptic effects (1.25, 2.5, and 5 mg/kg, i.p.), both Delta(9)-THC and Delta(8)-THC showed a U-shaped dose response with only Delta(9)-THC showing significant antidepressant-like effects at 2.5 mg/kg (p<0.05) in the FST. The cannabinoids cannabigerol (CBG) and cannabinol (CBN) did not produce antidepressant-like actions up to 80 mg/kg in the mouse FST, while cannabichromene (CBC) and cannabidiol (CBD) exhibited significant effect at 20 and 200mg/kg, respectively (p<0.01). The antidepressant-like action of Delta(9)-THC and CBC was further confirmed in the TST. Delta(9)-THC exhibited the same U-shaped dose response with significant antidepressant-like action at 2.5 mg/kg (p<0.05) while CBC resulted in a significant dose-dependent decrease in immobility at 40 and 80 mg/kg doses (p<0.01). Results of this study show that Delta(9)-THC and other cannabinoids exert antidepressant-like actions, and thus may contribute to the overall mood-elevating properties of cannabis. PMID:20332000

El-Alfy, Abir T; Ivey, Kelly; Robinson, Keisha; Ahmed, Safwat; Radwan, Mohamed; Slade, Desmond; Khan, Ikhlas; ElSohly, Mahmoud; Ross, Samir

2010-06-01

86

Relations between cannabis use and dependence, motives for cannabis use and anxious, depressive and borderline symptomatology  

Microsoft Academic Search

This study investigated the relations between anxious, depressive and borderline symptomatology, motivations for cannabis use, and cannabis use and dependence among 212 adolescents and young adults, 114 of whom were cannabis users. Motives for cannabis use were assessed using the Marijuana Motives Measure (Simons, J., Correia, C. J., Carey, K. B., & Borsari, B. E. (1998). Validating a Five-Factor Motives

Henri Chabrol; Emmanuelle Ducongé; Carine Casas; Charlotte Roura; Kate B. Carey

2005-01-01

87

[Cannabis smoking and lung cancer].  

PubMed

Cannabis is the most commonly smoked illicit substance in the world. It can be smoked alone in plant form (marijuana) but it is mainly smoked mixed with tobacco. The combined smoking of cannabis and tobacco is a common-place phenomenon in our society. However, its use is responsible for severe pulmonary consequences. The specific impact of smoking cannabis is difficult to assess precisely and to distinguish from the effect of tobacco. Marijuana smoke contains polycyclic aromatic hydrocarbons and carcinogens at higher concentration than tobacco smoke. Cellular, tissue, animal and human studies, and also epidemiological studies, show that marijuana smoke is a risk factor for lung cancer. Cannabis exposure doubles the risk of developing lung cancer. This should encourage clinicians to identify cannabis use and to offer patients support in quitting. PMID:25012035

Underner, M; Urban, T; Perriot, J; de Chazeron, I; Meurice, J-C

2014-06-01

88

Cannabis and Breastfeeding  

PubMed Central

Cannabis is a drug derived from hemp plant, Cannabis sativa, used both as a recreational drug or as medicine. It is a widespread illegal substance, generally smoked for its hallucinogenic properties. Little is known about the adverse effects of postnatal cannabis exposure throw breastfeeding because of a lack of studies in lactating women. The active substance of cannabis is the delta 9 TetraHydroCannabinol (THC). Some studies conclude that it could decrease motor development of the child at one year of age. Therefore, cannabis use and abuse of other drugs like alcohol, tobacco, or cocaine must be contraindicated during breastfeeding. Mothers who use cannabis must stop breastfeeding, or ask for medical assistance to stop cannabis use in order to provide her baby with all the benefits of human milk. PMID:20130780

Garry, Aurelia; Rigourd, Virginie; Amirouche, Ammar; Fauroux, Valerie; Aubry, Sylvie; Serreau, Raphael

2009-01-01

89

Cannabis and breastfeeding.  

PubMed

Cannabis is a drug derived from hemp plant, Cannabis sativa, used both as a recreational drug or as medicine. It is a widespread illegal substance, generally smoked for its hallucinogenic properties. Little is known about the adverse effects of postnatal cannabis exposure throw breastfeeding because of a lack of studies in lactating women. The active substance of cannabis is the delta 9 TetraHydroCannabinol (THC). Some studies conclude that it could decrease motor development of the child at one year of age. Therefore, cannabis use and abuse of other drugs like alcohol, tobacco, or cocaine must be contraindicated during breastfeeding. Mothers who use cannabis must stop breastfeeding, or ask for medical assistance to stop cannabis use in order to provide her baby with all the benefits of human milk. PMID:20130780

Garry, Aurélia; Rigourd, Virginie; Amirouche, Ammar; Fauroux, Valérie; Aubry, Sylvie; Serreau, Raphaël

2009-01-01

90

Hemp (Cannabis sativa L.) as a Resource for Green Cosmetics: Yield of Seed and Fatty Acid Compositions of 20 Varieties Under the Growing Conditions of Organic Farming in Austria  

Microsoft Academic Search

The interest in hemp (non-drug Cannabis sativa L.) for skin care and cosmetic use is due to the high content of oil, especially un- saturated fatty acids in seed with technological and therapeutic effects. In a field trial on an organic farm, seed weight and content of fatty acids

Christian R. Vogl; Helga Mölleken; Gunilla Lissek-Wolf; Andreas Surböck; Jörg Kobert

91

Technologically indicative properties of straw fractions of flax, linseed (Linum usitatissimum L.) and fibre hemp (Cannabis sativa L.).  

PubMed

In this study of the behaviour of the fractions of unretted and frost-retted fibre straws in damp air, a production scale method to separate fibre and shive from fibre plants was introduced and tested on bast fibre plants (Linum usitatissimum L. and Cannabis sativa L.). The method consists of optional drying of stalks, unloading bales, milling the straws with a hammer mill, separating the fractions from air stream with a cyclone and finally separating fibres from shives with a screening drum. Fractions were characterized focusing on technologically indicative properties such as equilibrium moisture content, ash and microbiological quality. Unretted fractions of the bast fibre plant stem reached higher equilibrium moisture contents than the retted fractions, and hemp fibres absorbed more moisture from air than did the Linum fibres. In very humid air, all fractions began to lose weight due to moulding. The weight decrease during the first week was lower in frost-retted than in unretted fractions. The frost-retted fractions appeared to be more resistant to humidity in the short term. The total number of microbes and especially the numbers of yeasts and moulds can be used as a criterion of hygienic level. For green fractions, the mould level was similar in fibres and in shives, but frost-retted shives contained more moulds than the unretted shives. The mould content of a fraction had no direct correlation with the moulding tendency of the fraction. The ash contents of fibres were somewhat higher than those of shives, due to a probable soil contamination. Ash content did not have significant correlation with microbiological quality, although ash is a possible risk factor for hygienic quality. According to the results of this study it is highly important to study the quality of the production chain of bast fibre plants to ensure the quality of industrial products. From the producer's point of view, raw material with defined quality can be directed to the most suitable application. The behaviour of fractions in various ambient atmospheres, and other quality aspects such as hygienic level can be used as criteria for defining the most appropriate product applications. PMID:15081488

Kymäläinen, H-R; Koivula, M; Kuisma, R; Sjöberg, A-M; Pehkonen, A

2004-08-01

92

Cannabis and Eicosanoids  

Microsoft Academic Search

Many constituents of cannabis exhibit beneficial anti-inflammatory properties, such as ? -tetrahydrocannabinol (THC) in marijuana and gamma-linolenic acid (GLA) in hemp seed oil. The effects of these cannabis constituents on eicosanoid metabolism is reviewed. THC and GLA modulate the arachidonic acid cascade, inhibiting the production of series 2 prostaglandins and series 4 leukotrienes. Canna-binoid receptor — as well as non-receptor-mediated

John M. McPartland

2001-01-01

93

Marijuana: Modern Medical Chimaera  

ERIC Educational Resources Information Center

Marijuana has been used medically since antiquity. In recent years there has been a resurgence of interest in medical applications of various cannabis preparations. These drugs have been cited in the medical literature as potential secondary treatment agents for severe pain, muscle spasticity, anorexia, nausea, sleep disturbances, and numerous…

Lamarine, Roland J.

2012-01-01

94

Randomized Controlled Trial of Motivational Enhancement Therapy With Nontreatment-Seeking Adolescent Cannabis Users: A Further Test of the Teen Marijuana Check-Up  

Microsoft Academic Search

Cannabis use adversely affects adolescents and interventions that are attractive to adolescents are needed. This trial compared the effects of a brief motivational intervention for cannabis use with a brief educational feedback control and a no-assessment control. Participants were randomized into one of three treatment conditions: Motivational Enhancement Therapy (MET), Educational Feedback Control (EFC), or Delayed Feedback Control (DFC). Those

Denise D. Walker; Robert Stephens; Roger Roffman; Josephine DeMarce; Brian Lozano; Sheri Towe; Belinda Berg

2011-01-01

95

Dutch Measures to Control Medical Grade Marijuana: Facilitating Clinical Trials  

Microsoft Academic Search

There is an emerging interest in the clinical use of cannabis (marijuana), but there is almost no evidence of its efficacy. The Dutch government has a policy that aims at collecting clinical data to determine whether cannabis can be used as a medicine. An Office of Medicinal Cannabis was established in March 2000. This office will act as a regulator

Willem K. Scholten

2001-01-01

96

Facts on Marijuana. Clearinghouse Fact Sheet.  

ERIC Educational Resources Information Center

Marijuana or Cannabis is a weed which grows in many different parts of the world. The plant may be altered into different forms to allow various forms of ingestion. Although marijuana's psychoactive properties have been known for almost 5,000 years, the plant first attracted public attention in the United States during the first half of this…

Brick, John

97

Medical marijuana users in substance abuse treatment  

Microsoft Academic Search

BACKGROUND: The rise of authorized marijuana use in the U.S. means that many individuals are using cannabis as they concurrently engage in other forms of treatment, such as substance abuse counseling and psychotherapy. Clinical and legal decisions may be influenced by findings that suggest marijuana use during treatment serves as an obstacle to treatment success, compromises treatment integrity, or increases

Ronald Swartz

2010-01-01

98

General and oral health implications of cannabis use  

Microsoft Academic Search

Cannabis, commonly known as marijuana, is the most frequently used illicit drug in Australia. Therefore, oral health care providers are likely to encounter patients who are regular users. An upward trend in cannabis use is occurring in Australia, with 40 per cent of the population aged 14 and above having used the drug. There are three main forms of cannabis:

CM Cho; R. Hirsch; S. Johnstone

2005-01-01

99

A PCR marker linked to a THCA synthase polymorphism is a reliable tool to discriminate potentially THC-rich plants of Cannabis sativa L.  

PubMed

Neither absolute THC content nor morphology allows the unequivocal discrimination of fiber cultivars and drug strains of Cannabis sativa L. unequivocally. However, the CBD/THC ratio remains constant throughout the plant's life cycle, is independent of environmental factors, and considered to be controlled by a single locus (B) with two codominant alleles (B(T) and B(D)). The homozygous B(T)/B(T) genotype underlies the THC-predominant phenotype, B(D)/B(D) is CBD predominant, and an intermediate phenotype is induced by the heterozygous state (B(T)/B(D)). Using PCR-based markers in two segregating populations, we proved that the THCA synthase gene represents the postulated B locus and that specific sequence polymorphisms are absolutely linked either to the THC-predominant or the THC-intermediate chemotype. The absolute linkage provides an excellent reliability of the marker signal in forensic casework. For validation, the species-specific marker system was applied to a large number of casework samples and fiber hemp cultivars. PMID:24579739

Staginnus, Christina; Zörntlein, Siegfried; de Meijer, Etienne

2014-07-01

100

Marijuana: modern medical chimaera.  

PubMed

Marijuana has been used medically since antiquity. In recent years there has been a resurgence of interest in medical applications of various cannabis preparations. These drugs have been cited in the medical literature as potential secondary treatment agents for severe pain, muscle spasticity, anorexia, nausea, sleep disturbances, and numerous other uses. This article reviews the research literature related to medical applications of various forms of cannabis. Benefits related to medical use of cannabinoids are examined and a number of potential risks associated with cannabis use, both medical and recreational, are considered. There is a clearly identified need for further research to isolate significant benefits from the medical application of cannabinoids and to establish dosage levels, appropriate delivery mechanisms and formulations, and to determine what role, if any, cannabinoids might play in legitimate medical applications. It is also imperative to determine if reported dangers pose a significant health risks to users. PMID:22873011

Lamarine, Roland J

2012-01-01

101

The Future of Medical Marijuana  

Microsoft Academic Search

SummaryThe medical value of marijuana is becoming increasingly clear, as it proves to be a remarkably versatile, safe, and inexpensive drug. Arrangements now being proposed for making cannabis constituents medically available include quasi-legal buyers clubs, restrictive classification as a prescription drug, the isolation of individual cannabinoids, and the manufacture of synthetic analogs. Careful analysis potentially of this inexpensive drug shows

L. Grinspoon

1999-01-01

102

Self-Reported Marijuana Effects and Characteristics of 100 San Francisco Medical Marijuana Club Members  

Microsoft Academic Search

In order to assess the relationships between medical marijuana users' reasons for use, side effects, and drug use patterns, 100 participants were recruited from the San Francisco Cannabis Cultivator's Club. Users, averaging 14 years pre-illness use, perceived marijuana to be more effective than other treatments and to have less severe side effects. Urine drug assays showed recent use of other

Debra Harris; Reese T. Jones; Robin Shank; Rajneesh Nath; Emilio Fernandez; Kenneth Goldstein; John Mendelson

2000-01-01

103

Medicinal cannabis: rational guidelines for dosing.  

PubMed

The medicinal value of cannabis (marijuana) is well documented in the medical literature. Cannabinoids, the active ingredients in cannabis, have many distinct pharmacological properties. These include analgesic, anti-emetic, anti-oxidative, neuroprotective and anti-inflammatory activity, as well as modulation of glial cells and tumor growth regulation. Concurrent with all these advances in the understanding of the physiological and pharmacological mechanisms of cannabis, there is a strong need for developing rational guidelines for dosing. This paper will review the known chemistry and pharmacology of cannabis and, on that basis, discuss rational guidelines for dosing. PMID:15154108

Carter, Gregory T; Weydt, Patrick; Kyashna-Tocha, Muraco; Abrams, Donald I

2004-05-01

104

Marijuana mania.  

PubMed

Marijuana has been used for recreational, ceremonial, and medicinal purposes for thousands of years. Because marijuana is classified as an illegal drug and, little research has been done on its potential medical benefits. In May 1999, it became legal for the National Institute on Drug Abuse (NIDA), the only legal source for marijuana, to sell marijuana to privately funded researchers. This move may make research on marijuana more feasible. Many people believe marijuana is effective in treating pain, AIDS wasting syndrome (AWS), and nausea and vomiting, among other ailments. However, even doctors who recommend marijuana use do not advise smoking it. Other ways of taking marijuana, as well as possible side effects of marijuana use, are discussed. PMID:11366748

Syracopoulos, T

1999-01-01

105

Cannabis withdrawal in chronic cannabis users with schizophrenia  

PubMed Central

Background Chronic users of cannabis often report withdrawal symptoms after abstinence from use, but little is known about cannabis withdrawal in people with schizophrenia. Methods Cannabis use patterns and withdrawal symptoms in adults with schizophrenia who had at least weekly cannabis use before attempting to quit without formal treatment were assessed with the Marijuana Quit Questionnaire (MJQQ), a 176-item, semi-structured questionnaire. Results 120 participants, predominantly African–American (62.5%) and male (76.7%), met inclusion criteria. 20.1% reported that their first regular cannabis use (median age 15 years [range 8–48]) preceded their age at first psychotic symptoms (20 [4–50] years). Twenty (16.7%) participants met lifetime criteria for cannabis abuse; 98 (81.7%) met surrogate criteria for lifetime cannabis dependence. Withdrawal symptoms were reported by 113 (94.2%) participants, with 74.2% reporting ?4 symptoms. The most frequently reported withdrawal symptoms were craving for cannabis (59.2%), feeling anxious (52.57%), feeling bored (47.5%), feeling sad or depressed (45.8%), feeling irritable or jumpy (45.0%), feeling restless (43.3%), and trouble failing asleep (33.3%). One hundred-and-four (92.0%) participants took some action to relieve at least one of their withdrawal symptoms during their index-quit attempt, including 26 (23.0%) participants who reported resuming cannabis use. Conclusion Cannabis withdrawal is a clinically significant feature of cannabis use among people with schizophrenia, may serve as a negative reinforcer for relapse, and deserves greater attention in treatment and research. Clinical Trials registration NCT00679016. PMID:23146560

Boggs, Douglas L.; Kelly, Deanna L.; Liu, Fang; Linthicum, Jared A.; Turner, Hailey; Schroeder, Jennifer R.; McMahon, Robert P.; Gorelick, David A.

2013-01-01

106

Is Marijuana Medicine?  

MedlinePLUS

... marijuana’s use for certain medical conditions. The term “medical marijuana” is generally used to refer to the whole ... produced by eating or smoking marijuana leaves. Are “Medical” and “Street” Marijuana Different? In principle, no. Most marijuana sold in ...

107

Immediate Antecedents of Marijuana Use: An Analysis from Ecological Momentary Assessment  

PubMed Central

Background and Objectives Marijuana remains the most commonly used illicit substance. Marijuana craving, anxiety, and peer marijuana use are thought to play important roles in the etiology and maintenance of marijuana use. The present study aimed to identify patterns between marijuana use and these affective and situational risk factors in the natural environment. Methods The sample consisted of 49 current marijuana users (38.8% female), 63.2% of whom evinced a current cannabis use disorder. Ecological momentary assessment was used to collect multiple daily ratings of marijuana craving, state anxiety, and peer marijuana use over two weeks. Mixed effects linear models were used to examine within- and between-day antecedents, correlates, and consequences of marijuana use. Results Between-day analyses indicated that marijuana use days were associated with higher marijuana craving but lower state anxiety. Within-day analyses confirmed that marijuana craving was higher prior to marijuana use and lower following use. Anxiety was related to marijuana craving. Although anxiety was somewhat higher prior to marijuana use, it did not decrease significantly following use. The vast majority of marijuana use occurred when others were also using marijuana. Limitations The sample was comprised of college students, a group at particular risk for marijuana use and use-related problems. Future work is necessary to determine whether results generalize to other populations. Conclusions These data support the contention that marijuana craving, anxiety, and peer use play important roles in the maintenance of marijuana use. PMID:21946296

Buckner, Julia D.; Crosby, Ross D.; Silgado, Jose; Wonderlich, Stephen A.; Schmidt, Norman B.

2011-01-01

108

Medical marijuana: clearing away the smoke.  

PubMed

Recent advances in understanding of the mode of action of tetrahydrocannabinol and related cannabinoid in-gredients of marijuana, plus the accumulating anecdotal reports on potential medical benefits have spurred increasing re-search into possible medicinal uses of cannabis. Recent clinical trials with smoked and vaporized marijuana, as well as other botanical extracts indicate the likelihood that the cannabinoids can be useful in the management of neuropathic pain, spasticity due to multiple sclerosis, and possibly other indications. As with all medications, benefits and risks need to be weighed in recommending cannabis to patients. We present an algorithm that may be useful to physicians in determining whether cannabis might be recommended as a treatment in jurisdictions where such use is permitted. PMID:22629287

Grant, Igor; Atkinson, J Hampton; Gouaux, Ben; Wilsey, Barth

2012-01-01

109

Medical Marijuana  

MedlinePLUS

... the lower right-hand corner of the player. Medical Marijuana HealthDay August 26, 2014 Related MedlinePlus Pages Chronic ... the American Medical Association found that states with medical marijuana laws had an average 25% lower opiate overdose ...

110

Therapeutic Benefits of Cannabis: A Patient Survey  

PubMed Central

Clinical research regarding the therapeutic benefits of cannabis (“marijuana”) has been almost non-existent in the United States since cannabis was given Schedule I status in the Controlled Substances Act of 1970. In order to discover the benefits and adverse effects perceived by medical cannabis patients, especially with regards to chronic pain, we hand-delivered surveys to one hundred consecutive patients who were returning for yearly re-certification for medical cannabis use in Hawai‘i. The response rate was 94%. Mean and median ages were 49.3 and 51 years respectively. Ninety-seven per cent of respondents used cannabis primarily for chronic pain. Average pain improvement on a 0–10 pain scale was 5.0 (from 7.8 to 2.8), which translates to a 64% relative decrease in average pain. Half of all respondents also noted relief from stress/anxiety, and nearly half (45%) reported relief from insomnia. Most patients (71%) reported no adverse effects, while 6% reported a cough or throat irritation and 5% feared arrest even though medical cannabis is legal in Hawai‘i. No serious adverse effects were reported. These results suggest that Cannabis is an extremely safe and effective medication for many chronic pain patients. Cannabis appears to alleviate pain, insomnia, and may be helpful in relieving anxiety. Cannabis has shown extreme promise in the treatment of numerous medical problems and deserves to be released from the current Schedule I federal prohibition against research and prescription. PMID:24765558

Webb, Sandra M

2014-01-01

111

Cannabis; adverse effects from an oromucosal spray  

Microsoft Academic Search

Background An oromucosal spray has been developed from the major components of marijuana (cannabis), including tetrahydrocannabinol (THC) and cannabidiol (CBD), in alcohol with a peppermint flavouring, designed to be administered as a spray under the tongue or on the buccal mucosa to relieve pain in multiple sclerosis. Although the available evidence indicates its efficacy in this respect, some patients develop

C. Scully

2007-01-01

112

The intersection between cannabis and cancer in the United States.  

PubMed

In the last 15 years there has been a major shift in the laws governing medical use of cannabis in the United States. Corresponding with this change there has been escalating interest in the role that cannabis, commonly referred to as marijuana, and cannabinoids play in the care of patients with cancer. This review will examine cannabis' and cannabinoids' current and potential roles in cancer care. Specifically, we will examine five areas of cannabis medicine: (1) pharmacologic properties of cannabis; (2) its potential role in the development of human cancers, particularly smoking-related malignancies; (3) cannabinoids' potential as anti-cancer therapies; (4) cannabis and cannabinoids in the palliation of common cancer-associated symptoms; (5) current legal status of cannabis for medical purposes in the United States. PMID:22019199

Bowles, Daniel W; O'Bryant, Cindy L; Camidge, D Ross; Jimeno, Antonio

2012-07-01

113

Medical marijuana.  

PubMed

Although many clinical studies suggest the medical utility of marijuana for some conditions, the scientific evidence is weak. Many patients in California are self-medicating with marijuana, and physicians need data to assess the risks and benefits. The only reasonable solution to this problem is to encourage research on the medical effects of marijuana. The current regulatory system should be modified to remove barriers to clinical research with marijuana. The NIH panel has identified several conditions for which there may be therapeutic benefit from marijuana use and that merit further research. Marijuana should be held to the same evaluation standards of safety and efficacy as other drugs (a major flaw in Proposition 215) but should not have to be proved better than current medications for its use to be adopted. The therapeutic window for marijuana and THC between desired effect and unpleasant side effects is narrow and is a major reason for discontinuing use. Although the inhaled route of administration has the benefit of allowing patients to self-titrate the dose, the smoking of crude plant material is problematic. The NIH panel recommended that a high priority be given to the development of a controlled inhaled form of THC. The presence of a naturally occurring cannabinoid-receptor system in the brain suggests that research on selective analogues of THC may be useful to enhance its therapeutic effects and minimize adverse effects. PMID:9656007

Marmor, J B

1998-06-01

114

Medical marijuana.  

PubMed

Grassroots AIDS activist groups denounce the Clinton Administration's stance on banning medicinal use of marijuana due to the lack of clinical evidence supporting its benefits. The 1997 meeting of the San Francisco Medical Society and the New England Journal of Medicine both agreed, following a review of 75 scientific studies of the medicinal benefits of marijuana, that the benefits of smoked marijuana include relief from pain and the reduction of nausea caused by anti-cancer drugs. The Federal government is attempting to punish physicians for prescribing marijuana to their patients, a situation being opposed by the Bay Area Physicians for Human Rights who have initiated a suit against the government. A hearing to stop this prosecution was scheduled for March 21. PMID:11364533

Baker, R; Bowers, M

1997-03-01

115

Concomitant consumption of marijuana, alcohol and tobacco in oral squamous cell carcinoma development and progression: recent advances and challenges.  

PubMed

Oral squamous cell carcinoma (OSCC) corresponds to 95% of all malignant tumours of the mouth. The association between alcohol and tobacco is the major risk factor for this disease, increasing the chances for the development of OSCC by 35-fold. The plant, Cannabis sativa is smoked as cigarettes or blunts and is commonly used in association with tobacco and alcohol. Any type of smoking habit exposes individuals to a wide range of carcinogens or pro-carcinogens, such as polycyclic aromatic hydrocarbons, as well as some ethanol derived substances such as acetaldehyde (AA), and all are genotoxic in the same way. In addition, ethanol acts in the oral mucosa as a solvent and therefore increases the cellular membrane permeability to carcinogens. Carcinogens found in tobacco are also concentrated in marijuana, but the latter also contains high levels of cannabinoids, bioactive compounds responsible for several effects such as euphoria and analgesia. However, ?(9)-tetrahydrocannabinol (?(9)-THC), the major psychotropic cannabinoid found in plants, causes a reduction of cellular metabolism and induction of apoptosis, both of which are anti-neoplastic properties. Apart from limited epidemiologic and experimental data, the effects of concomitant chronic exposure to marijuana (or ?(9)-THC), tobacco and alcohol in OSCC development and progression is poorly known. This paper reviews the most recent findings on the effects of marijuana over cellular proliferation, as well as in the risk for OSCC, with emphasis on its interaction with tobacco and ethanol consumption. PMID:22727410

Lopes, Caio Fabio Baeta; de Angelis, Bruno Brandão; Prudente, Henrique Maciel; de Souza, Bernardo Vieira Goulart; Cardoso, Sérgio Vitorino; de Azambuja Ribeiro, Rosy Iara Maciel

2012-08-01

116

Aerobic Exercise Training Reduces Cannabis Craving and Use in Non-Treatment Seeking Cannabis-Dependent  

E-print Network

there are no approved medications for this condition, treatment must rely on behavioral approaches empirically­70% HR reserve) over 2 weeks. Exercise sessions were conducted by exercise physiologists under medical the Marijuana Craving Questionnaire (MCQ-SF). Findings: Daily cannabis use within the run-in period was 5

Palmeri, Thomas

117

Multidimensional Family Therapy for Adolescent Cannabis Users, Cannabis Youth Treatment (CYT) Series, Volume 5.  

ERIC Educational Resources Information Center

The purpose of the Substance Abuse and Mental Health Services Administration's Center for Substance Abuse Treatment's (CSAT's) Cannabis Youth Treatment (CYT) Project Cooperative Agreement was to test the relative effectiveness and cost-effectiveness of a variety of interventions designed to eliminate marijuana use and associated problems in…

Liddle, Howard A.

118

Cannabis prices and dynamics of cannabis use  

Microsoft Academic Search

This paper uses duration models and self-reported cannabis histories from young Australians to study the dynamics of cannabis use. We find that low cannabis prices are associated with early initiation into cannabis use. While the decision to quit does not appear to be directly influenced by price, we find that the younger an individual is when they start using cannabis

Jenny Williams

2007-01-01

119

Intermediate cannabis dependence phenotypes and the FAAH C385A variant: an exploratory analysis  

Microsoft Academic Search

Rationale  Cannabis dependence is a growing problem among individuals who use marijuana frequently, and genetic differences make some\\u000a users more liable to progress to dependence. The identification of intermediate phenotypes of cannabis dependence may aid\\u000a candidate genetic analysis. Promising intermediate phenotypes include craving for marijuana, withdrawal symptoms after abstinence,\\u000a and sensitivity to its acute effects. A single nucleotide polymorphism (SNP) in

Joseph P. Schacht; Rebecca E. Selling; Kent E. Hutchison

2009-01-01

120

Medical Marijuana Laws and Teen Marijuana Use  

Microsoft Academic Search

While at least a dozen state legislatures are considering bills to allow the consumption of marijuana for medicinal purposes, the federal government has recently intensified its efforts to close medical marijuana dispensaries. Federal officials contend that the legalization of medical marijuana encourages teenagers to use marijuana and have targeted dispensaries operating within 1,000 feet of schools, parks and playgrounds. Using

D. Mark Anderson; Benjamin Hansen; Daniel I. Rees

2012-01-01

121

Cannabis: Psychological effects of chronic heavy use  

Microsoft Academic Search

The psychological effects of chronic heavy use of Cannabis sativa were studied in a population of normal adult Jamaican males. Users had been daily consumers of the drug for a minimum of 10 years; Controls were subjects who had neither current nor past experience with the drug. Subjects were matched for age, sex, social class, alcohol use, level of general

Marilyn Bowman; Robert O. Pihl

1973-01-01

122

Increased Exposure to Alcohol and Cannabis Education and Changes in Use Patterns.  

ERIC Educational Resources Information Center

Used data from Ontario Alcohol and Drug Use Among Students survey (N=4,267) to determine how reported alcohol and cannabis (marijuana) use changed with increased exposure to drug education. Concluded drug education had stronger influence on younger students and lighter drinkers but little impact on heavy drinkers. Found decrease in cannabis use…

Smart, Reginald G.

1989-01-01

123

Short scales to assess cannabis-related problems: a review of psychometric properties  

Microsoft Academic Search

AIMS: The purpose of this paper is to summarize the psychometric properties of four short screening scales to assess problematic forms of cannabis use: Severity of Dependence Scale (SDS), Cannabis Use Disorders Identification Test (CUDIT), Cannabis Abuse Screening Test (CAST) and Problematic Use of Marijuana (PUM). METHODS: A systematic computer-based literature search was conducted within the databases of PubMed, PsychINFO

Daniela Piontek; Ludwig Kraus; Danica Klempova

2008-01-01

124

Progression from marijuana use to daily smoking and nicotine dependence in a national sample of U.S. adolescents  

Microsoft Academic Search

BackgroundWhile it has been demonstrated that smoking cigarettes in adolescence increases the likelihood of progressing to marijuana use, few studies have considered the reverse scenario in which early use of cannabis leads to greater tobacco smoking.

David S. Timberlake; Brett C. Haberstick; Christian J. Hopfer; Josh Bricker; Joseph T. Sakai; Jeffrey M. Lessem; John K. Hewitt

2007-01-01

125

Costs of compassion club marijuana to be covered.  

PubMed

In 2010, the Appeals Tribunal of the Workplace Safety and Insurance Board (WSIB) of Ontario held that Gary Simpson's cannabis costs should be reimbursed. Simpson sustained an acute back injury in 2000 while working as a heavy equipment mechanic. In 2003, Health Canada approved his application for medical marijuana. PMID:22165273

2011-10-01

126

Marijuana Primes, Marijuana Expectancies, and Arithmetic Efficiency*  

PubMed Central

Objective: Previous research has shown that primes associated with alcohol influence behavior consistent with specific alcohol expectancies. The present study examined whether exposure to marijuana-related primes and marijuana expectancies interact to produce similar effects. Specifically, the present study examined whether marijuana primes and marijuana expectancies regarding cognitive and behavioral impairment interact to influence performance on an arithmetic task. Method: Two independent samples (N = 260) of undergraduate students (both marijuana users and nonusers) first completed measures of marijuana-outcome expectancies associated with cognitive and behavioral impairment and with general negative effects (Sample 2). Later in the semester, participants were exposed to marijuana-related (or neutral) primes and then completed an arithmetic task. Results: Results from Sample 1 indicated that participants who were exposed to marijuana-themed magazine covers performed more poorly on the arithmetic task if they expected that marijuana would lead to cognitive and behavioral impairment. Results from Sample 2 indicated that, for marijuana users, cognitive and behavioral impairment expectancies, but not expectancies regarding general negative effects, similarly moderated arithmetic performance for participants exposed to marijuana-related words. Conclusions: Results support the hypothesis that the implicit activation of specific marijuana-outcome expectancies can influence cognitive processes. Implications for research on marijuana are discussed. PMID:19371490

Hicks, Joshua A.; Pedersen, Sarah L.; McCarthy, Denis M.; Friedman, Ronald S.

2009-01-01

127

[Brain effects of cannabis--neuroimaging findings].  

PubMed

Cannabis is the most widely used illicit drug. Despite this, only a small number of studies have investigated the long-term neurotoxic consequences of cannabis use. Structural and functional neuroimaging techniques are powerful research tools to investigate possible cannabis-induced pathophysiological changes. A computer literature review was conducted in the MEDLINE and PsycLIT databases between 1966 and November of 2004 with the search terms 'cannabis', 'marijuana', 'neuroimaging', 'magnetic resonance', 'computed tomography', 'positron emission tomography', 'single photon emission computed tomography", 'SPET', 'MRI' and 'CT'. Structural neuroimaging studies have yielded conflicting results. Most studies report no evidence of cerebral atrophy or regional changes in tissue volumes, and one study suggested that long-term users who started regular use on early adolescence have cerebral atrophy as well as reduction in gray matter. However, several methodological shortcomings limit the interpretation of these results. Functional neuroimaging studies have reported increases in neural activity in regions that may be related with cannabis intoxication or mood-change effects (orbital and mesial frontal lobes, insula, and anterior cingulate) and decreases in activity of regions related with cognitive functions impaired during acute intoxication. The important question whether residual neurotoxic effects occur after prolonged and regular use of cannabis remains unclear, with no study addressing this question directly. Better designed neuroimaging studies, combined with cognitive evaluation, may be elucidative on this issue. PMID:15867988

Crippa, José Alexandre; Lacerda, Acioly L T; Amaro, Edson; Busatto Filho, Geraldo; Zuardi, Antonio Waldo; Bressan, Rodrigo A

2005-03-01

128

Cannabis: discrimination of "internal bliss"?  

PubMed

The recent discovery of arachidonylethanolamide (anandamide), an endogenous ligand for cannabinoid receptors, and the synthesis of SR141716A, a cannabinoid antagonist selective for brain cannabinoid (CB1) receptors, have provided new tools to explore the mechanisms underlying cannabis abuse and dependence. Drug discrimination is the animal model with the most predictive validity and specificity for investigation of the psychoactive effects of cannabinoids related to their abuse potential, because, unlike many other drugs of abuse, delta9-tetrahydrocannabinol (delta9-THC), the major psychoactive ingredient of marijuana, is not self-administered by animals. Results of delta9-THC discrimination studies have revealed that the subjective effects of cannabis intoxication are pharmacologically selective for centrally active cannabinoid compounds, and that cannabis action at CB1 receptors is involved in medication of these effects. Less clear is the role of endogenous cannabinoid system(s) in cannabis intoxication. Anandamide, named for a Sanskrit word for "internal bliss," unreliably substitutes for delta9-THC. Further, substitution, when it is observed, occurs only at doses that also significantly decrease response rates. In contrast, delta9-THC and other structurally diverse cannabinoids fully substitute for delta9-THC at doses that do not substantially affect response rates. Attempts to train animals to discriminate anandamide (or SR141716A) have so far been unsuccessful. Preliminary evidence from drug discrimination studies with more metabolically stable anandamide analogs have suggested that these differences in the discriminative stimulus effects of delta9-THC and anandamide-like cannabinoids are not entirely due to pharmacokinetic factors, but the exact role of "internal bliss" in cannabis intoxication and dependence is still not completely understood. PMID:10515300

Wiley, J L

1999-10-01

129

Myocardial infarction following cannabis induced coronary vasospasm.  

PubMed

Smoking cannabis is a rare cause of myocardial infarction. We report a 29-year-old man who presented with acute coronary syndrome following consumption of a type of cannabis with the street name 'Kerala Ganja'. KG is smuggled into Sri Lanka from India; it is grown in the south Indian state of Kerala and is much more potent than the local ganja (marijuana). The patient developed dynamic ST-segment elevations in different leads in sequential ECGs, corresponding to different coronary artery territories. Coronary angiogram did not demonstrate evidence of occlusive atherosclerotic disease, but showed slow flow down the left anterior descending artery, which improved with administration of intracoronary nitrates. The patient's cardiac biomarkers were significantly elevated. A diagnosis was made of vasospasm causing myocardial infarction, most likely to have been triggered by cannabis consumption. We highlight the importance of considering this possible aetiology, particularly in patients with ACS with a susceptible social profile. PMID:25391827

Gunawardena, Mudalige Don Vajira Malin; Rajapakse, Senaka; Herath, Jagath; Amarasena, Naomali

2014-01-01

130

Marijuana as doping in sports.  

PubMed

A high incidence of positive cases for cannabinoids, in analyses for doping control in sports, has been observed since the International Olympic Committee (IOC) included them in the 1989 list of prohibited drugs under the title of classes of prohibited substances in certain circumstances. Where the rules of sports federations so provide, tests are conducted for marijuana, hashish or any other cannabis product exposure by means of urinalysis of 11-nor-delta-9-tetrahydrocannabinol-9-carboxylic acid (carboxy-THC) the main metabolite of delta-9-tetrahydrocannabinol (THC). Concentrations >15 ng/mL (cut-off value) in confirmatory analytical procedures are considered doping. Cannabis is an illicit drug in several countries and has received much attention in the media for its potential therapeutic uses and the efforts to legalise its use. Studies have demonstrated that the use of cannabinoids can reduce anxiety, but it does not have ergogenic potential in sports activities. An increase in heart rate and blood pressure, decline of cardiac output and reduced psychomotor activity are some of the pharmacological effects of THC that will determine a decrease in athletic performance. An ergolytic activity of cannabis products has been observed in athletes of several different sport categories. In Brazil, analyses for doping control in sports, performed in our laboratories, have detected positive cases for carboxy-THC in urine samples of soccer, volleyball, cycling and other athletes. It is our intention to discuss in this article some points that may discourage individuals from using cannabis products during sports activities, even in the so-called permitted circumstances defined by the IOC and some sports federations. PMID:12744713

Campos, Daniel R; Yonamine, Mauricio; de Moraes Moreau, Regina L

2003-01-01

131

Medical marijuana.  

PubMed

The Florida Supreme Court heard oral arguments in April regarding a glaucoma patient's request for a medical exception to the State prohibition on use of marijuana. [Name removed] was convicted on possession and cultivation charges, and a trial judge refused to allow a medical necessity defense. A State appeals court subsequently overturned [name removed]'s conviction. The case focuses on whether the legislature intended to prohibit such a defense when it declared in 1993 that the substance had no medicinal benefits. PMID:11366533

1999-04-30

132

Women's Marijuana Problems  

Microsoft Academic Search

Individual, cultural, professional, and gender-related factors converge to increase the denial of women's marijuana problems. Recent epidemiological information on marijuana use shows that marijuana is a significant problem for women of various ethnic groups, pregnant women, young adults and workers. Women's marijuana-related problems affect their health, safety, domestic relations, motherhood, and work. Outdated addiction theories, diagnostic tools, and insufficient research

Susan Chacín

1996-01-01

133

Differential Effects of Medical Marijuana Based on Strain and Route of Administration  

Microsoft Academic Search

Cannabis displays substantial effectiveness for a variety of medical symptoms. Seventy-seven patients took part in a study in California to assess the efficacy of organically grown Cannabis sativa and indica strains in treatment of various medical conditions via smoking or ingestion. HIV\\/AIDS was the most frequent condition reported, at 51%. Standardized rating forms provided 1892 records that were statistically analyzed.

Valerie Leveroni Corral

2001-01-01

134

Menace or medicine? Anthropological perspectives on the self-administration of high potency cannabis in the UK  

Microsoft Academic Search

Domestically produced, high potency cannabis (often referred to as ‘skunk’ in the mainstream UK media) has become increasingly widespread in the UK. This paper considers whether the trend reflects an increased awareness of and desire for medical marijuana. Determining whether cannabis is a drug or a medicine depends on its objective physiological effects - which may vary from one individual

Anna Waldstein

2010-01-01

135

Role of cannabis and endocannabinoids in the genesis of schizophrenia  

Microsoft Academic Search

Rationale  Cannabis abuse and endocannabinoids are associated to schizophrenia.\\u000a \\u000a \\u000a \\u000a Objectives  It is important to discern the association between schizophrenia and exogenous Cannabis sativa, on one hand, and the endogenous cannabinoid system, on the other hand.\\u000a \\u000a \\u000a \\u000a Results  On one hand, there is substantial evidence that cannabis abuse is a risk factor for psychosis in genetically predisposed people,\\u000a may lead to a worse outcome of

Emilio Fernandez-Espejo; Maria-Paz Viveros; Luis Núñez; Bart A. Ellenbroek; Fernando Rodriguez de Fonseca

2009-01-01

136

Cannabis finds its way into treatment of Crohn's disease.  

PubMed

In ancient medicine, cannabis has been widely used to cure disturbances and inflammation of the bowel. A recent clinical study now shows that the medicinal plant Cannabis sativa has lived up to expectations and proved to be highly efficient in cases of inflammatory bowel diseases. In a prospective placebo-controlled study, it has been shown what has been largely anticipated from anecdotal reports, i.e. that cannabis produces significant clinical benefits in patients with Crohn's disease. The mechanisms involved are not yet clear but most likely include peripheral actions on cannabinoid receptors 1 and 2, and may also include central actions. PMID:24356243

Schicho, Rudolf; Storr, Martin

2014-01-01

137

Endocannabinoids in the Retina: From Marijuana to Neuroprotection  

PubMed Central

The active component of the marijuana plant Cannabis sativa, ?9-tetrahydrocannabinol (THC), produces numerous beneficial effects, including analgesia, appetite stimulation and nausea reduction, in addition to its psychotropic effects. THC mimics the action of endogenous fatty acid derivatives, referred to as endocannabinoids. The effects of THC and the endocannabinoids are mediated largely by metabotropic receptors that are distributed throughout the nervous and peripheral organ systems. There is great interest in endocannabinoids for their role in neuroplasticity as well as for therapeutic use in numerous conditions, including pain, stroke, cancer, obesity, osteoporosis, fertility, neurodegenerative diseases, multiple sclerosis, glaucoma and inflammatory diseases, among others. However, there has been relatively far less research on this topic in the eye and retina compared with the brain and other organ systems. The purpose of this review is to introduce the “cannabinergic” field to the retinal community. All of the fundamental work on cannabinoids has been performed in non-retinal preparations, necessitating extensive dependence on this literature for background. Happily, the retinal cannabinoid system has much in common with other regions of the central nervous system. For example, there is general agreement that cannabinoids suppress dopamine release and presynaptically reduce transmitter release from cones and bipolar cells. How these effects relate to light and dark adaptation, receptive field formation, temporal properties of ganglion cells or visual perception are unknown. The presence of multiple endocannabinoids, degradative enzymes with their bioactive metabolites, and receptors provides a broad spectrum of opportunities for basic research and to identify targets for therapeutic application to retinal diseases. PMID:18725316

Yazulla, Stephen

2008-01-01

138

A survey of the potency of Japanese illicit cannabis in fiscal year 2010.  

PubMed

In recent years, increased 'cannabis potency', or ?(9)-tetrahydrocannabinol (THC) content in cannabis products, has been reported in many countries. A survey of Japanese illicit cannabis was conducted from April 2010 to March 2011. In Japan, all cannabis evidence is transferred to the Minister of Health, Labour and Welfare after criminal trials. The evidence was observed at Narcotics Control Department offices in major 11 cities. The total number of cannabis samples observed was 9072, of which 6376 were marijuana. The marijuana seizures were further classified, and it was found that in terms of the number of samples, 65.2% of them were seedless buds, and by weight 73.0% of them were seedless buds. Seedless buds were supposed to be 'sinsemilla', a potent class of marijuana. THC, cannabinol (CBN) and cannabidiol (CBD) in marijuana seizures exceeding 1g were quantified. The number of samples analyzed was 1115. Many of them were shown to contain CBN, an oxidative product from THC. This was a sign of long-term storage of the cannabis and of the degradation of THC. Relatively fresh cannabis, defined by a CBN/THC ratio of less than or equal to 0.1, was chosen for analysis. Fresh seedless buds (335 samples) contained an average of 11.2% and a maximum of 22.6% THC. These values are comparable to those of 'high potency cannabis' as defined in previous studies. Thus, this study shows that highly potent cannabis products are distributed in Japan as in other countries. PMID:22554871

Tsumura, Yukari; Aoki, Rikiya; Tokieda, Yoshio; Akutsu, Mamoru; Kawase, Yasuharu; Kataoka, Tadashi; Takagi, Toshiyuki; Mizuno, Tomomi; Fukada, Masakatsu; Fujii, Hiroshi; Kurahashi, Kazumi

2012-09-10

139

Chromosome Aberrations Study in Human Lymphocytes from Marijuana Smokers  

Microsoft Academic Search

One of the main problems affecting our society nowadays is drug consumption. Hemp derivatives (Cannabis sativa) are the drugs most commonly abused by the young Chilean population. This product is obtained from the leaves and dried up flowers, they contains the active product, tetrahydrocannabinol, which is five to six times lower in concentration than that found in hashish (Florenzano et

M. A. García; G. Weigert; S. Duk; M. Alarcón

1999-01-01

140

Is today's marijuana more potent simply because it's fresher?  

PubMed

The average potency of illicit marijuana in the USA has increased substantially over the past four decades, and observers have suggested a number of likely reasons for this. One set of hypotheses points to a market that has evolved from foreign to domestic sources of supply, and to continuing advances in sophisticated cultivation techniques. Another set of hypotheses points to testing artifacts related to changes in the sampling, handling, and testing of illicit marijuana. The current study uses data from the federally sponsored Potency Monitoring Program, which performs ongoing forensic analysis of seized marijuana samples, to assess the extent to which the observed increase in cannabis potency in the USA between 1970 and 2010 is a function of genuine shifts in illicit marijuana markets or testing artifacts related to changes in the quality of seized marijuana. The study finds, after adjusting for marijuana quality, that the apparent 10.5 factor increase in mean reported THC% between the 1970s and the 2000s is instead on the order of a six- to seven-fold increase. By this accounting, then, the reported long-term rise in potency is roughly 57-67% as great when the quality of the tested marijuana is taken into account. This study's findings, therefore, caution against the uncritical use of potency monitoring data and highlight the importance of assessing potency measurement reliability and addressing data quality issues in future policy analytic research. PMID:23169764

Sevigny, Eric L

2013-01-01

141

Does liberalizing cannabis laws increase cannabis use?  

PubMed

A key question in the ongoing policy debate over cannabis' legal status is whether liberalizing cannabis laws leads to an increase in cannabis use. This paper provides new evidence on the impact of a specific type of liberalization, decriminalization, on initiation into cannabis use. Our identification strategy exploits variation in the timing of cannabis policy reforms and our estimation framework marries a difference-in-difference approach with a discrete time duration model. Our results reveal evidence of both heterogeneity and dynamics in the response of cannabis uptake to decriminalization. Overall, we find that the impact of decriminalization is concentrated amongst minors, who have a higher rate of uptake in the first five years following its introduction. PMID:24727348

Williams, Jenny; Bretteville-Jensen, Anne Line

2014-07-01

142

Cannabis sativa : an optimization study for ROI  

E-print Network

Despite hemp's multifarious uses in over 30 countries ranging from the manufacture of paper to specialty textiles, construction, animal feed, and fuel, its acceptance in the US has been shunned because of its association ...

Esmail, Adnan M

2010-01-01

143

Primary Outcomes in Two Randomized Controlled Trials of Treatments for Cannabis Use Disorders  

PubMed Central

Background While several randomized controlled trials evaluating a range of treatments for cannabis use disorders have appeared in recent years, these have been marked by inconsistency in selection of primary outcomes, making it difficult to compare outcomes across studies. Method With the aim of identifying meaningful and reliable outcome domains in treatment studies of cannabis use disorders, we evaluated multiple indicators of marijuana use, marijuana problems, and psychosocial functioning from two independent randomized controlled trials of behavioral treatments for cannabis use disorders (Ns = 450 and 136). Results Confirmatory factor analysis indicated that the best-fitting model of outcomes in both trials encompassed three distinct factors: frequency of marijuana use, severity of marijuana use, and psychosocial functioning. In both trials, frequency of marijuana use and longest period of abstinence during treatment were most strongly associated with outcome during follow-up. Using two categorical definitions of “clinically-significant improvement,” individuals who demonstrated improvement differed on most end-of-treatment and long-term outcomes from those who did not improve. Conclusions Results may guide future randomized controlled trials of treatments for cannabis use disorders in the collection of relevant end-of-treatment outcomes and encourage consistency in the reporting of outcomes across trials. PMID:21620591

Peters, Erica N.; Nich, Charla; Carroll, Kathleen M.

2011-01-01

144

An open-label pilot study of cannabis-based extracts for bladder dysfunction in advanced multiple sclerosis  

Microsoft Academic Search

The majority of patients with multiple sclerosis (MS) develop troublesome lower urinary tract symptoms (LUTS). Anecdotal reports suggest that cannabis may alleviate LUTS, and cannabinoid receptors in the bladder and nervous system are potential pharmacological targets. In an open trial we evaluated the safety, tolerability, dose range, and efficacy of two whole-plant extracts of Cannabis sativa in patients with advanced

CM Brady; R Dasgupta; C Dalton; OJ Wiseman; KJ Berkley; CJ Fowler

2004-01-01

145

Marijuana Neurobiology and Treatment  

PubMed Central

Marijuana is the number one illicit drug of abuse worldwide and a major public health problem, especially in the younger population. The objective of this article is to update and review the state of the science and treatments available for marijuana dependence based on a pre-meeting workshop that was presented at ISAM 2006. At the workshop, several papers were presented addressing the neurobiology and pharmacology of marijuana and treatment approaches, both psychotherapy and medications, for marijuana withdrawal. Medicolegal and ethical issues concerning marijuana medical use were also discussed. Concise summaries of these presentations are incorporated in this article, which is meant to be an updated review of the state of the science. Major advances have been made in understanding the underpinning of marijuana dependence and the role of the CNS cannabinoid system, which is a major area for targeting medications to treat marijuana withdrawal and dependence, as well as other addictions. Behavioral therapies are efficacious for facilitating abstinence from marijuana. Nefazadone, Marinol, and buspirone are showing early positive signals for efficacy in ameliorating marijuana withdrawal symptoms. Effective psychotherapeutic approaches are available and promising medications studies need to be confirmed in outpatient trials. The next few years looking promising for translational research efforts to make treatment widely accessible to patients with marijuana dependence. PMID:19042204

Elkashef, Ahmed; Vocci, Frank; Huestis, Marilyn; Haney, Margaret; Budney, Alan; Gruber, Amanda; el-Guebaly, Nady

2008-01-01

146

Marijuana as medicine.  

PubMed

A Pierce County judge has ruled that physicians can prescribe marijuana for medical purposes. Judge Rosanne Buckner decided that lawyer [name removed], who is undergoing treatment for bone cancer, can use marijuana to ease the pain associated with chemotherapy. Buckner ruled that the patient's interest in using marijuana as a medicine outweighs Washington's interest in outlawing prescriptions for it. Assistant Attorney General Melissa Burke-Cain plans to appeal this decision. PMID:11362944

1995-12-01

147

Vaporizers for medical marijuana.  

PubMed

A major concern about the medical use of marijuana is the harmful effects that come from smoking it. Vaporizers are designed to release the active ingredients in marijuana without burning it, and therefore do not release the harmful substances found in the marijuana smoke. The Institute of Medicine recommends against the long-term medical use of smoked marijuana because of carcinogens and other chemicals in the smoke. Several vaporizers are on the market, but they have not been tested in the laboratory yet. A review of two vaporizers is given. Contact information is provided. PMID:11366582

Mirken, B

1999-09-17

148

The toxicology of cannabis and cannabis prohibition.  

PubMed

The acute side effects caused by cannabis use are mainly related to psyche and cognition, and to circulation. Euphoria, anxiety, changes in sensory perception, impairment of memory and psychomotor performance are common effects after a dose is taken that exceeds an individually variable threshold. Cannabis consumption may increase heart rate and change blood pressure, which may have serious consequences in people with heart disease. Effects of chronic use may be induction of psychosis and development of dependency to the drug. Effects on cognitive abilities seem to be reversible after abstinence, except possibly in very heavy users. Cannabis exposure in utero may have negative consequences on brain development with subtle impairment of cognitive abilities in later life. Consequences of cannabis smoking may be similar to those of tobacco smoking and should be avoided. Use by young people has more detrimental effects than use by adults. There appear to be promising therapeutic uses of cannabis for a range of indications. Use of moderate doses in a therapeutic context is usually not associated with severe side effects. Current prohibition on cannabis use may also have harmful side effects for the individual and the society, while having little influence on prevalence of use. Harm is greatest for seriously ill people who may benefit from a treatment with cannabis. This makes it difficult to justify criminal penalties against patients. PMID:17712818

Grotenhermen, Franjo

2007-08-01

149

Assessing marijuana use in bariatric surgery candidates: should it be a contraindication?  

PubMed

Research has demonstrated negative effects of both alcohol and tobacco use after bariatric surgery. However, no research to date has examined effects of cannabis use after bariatric surgery, even though cannabis is the most commonly used illicit drug in the USA. Literature review reveals that many practitioners generalize from data regarding alcohol abuse to all substances. Further, many screening protocols fail to differentiate between varying levels of cannabis use. The current report aims to (1) review the relevant literature on marijuana use and its potential consequences among bariatric patients, (2) discuss relevant problems and gaps in this literature, and (3) make preliminary recommendations regarding the assessment and treatment planning of bariatric candidates who disclose marijuana use. PMID:24913244

Rummell, Christina M; Heinberg, Leslie J

2014-10-01

150

Hemp for Headache: An In-Depth Historical and Scientific Review of Cannabis in Migraine Treatment  

Microsoft Academic Search

Cannabis, or ''marijuana,'' has been employed in various forms throughout the millennia for both symptomatic and prophylactic treatment of migraine. This document examines its history of medicinal use by smoking and other methods in ancient cultures, including the Chinese, Indian, Egyptian, Assyrian, Greek and Roman, as well as in the Islamic world, and its subsequent adoption by Renaissance and Industrial

Ethan Russo

151

Position Paper: Should the Scottish National Party Support Scotland to Legalize, Decriminalize, or Prohibit Cannabis?  

ERIC Educational Resources Information Center

The UK has the highest rate of cannabis use among young people worldwide. Dr. Alan Leshner, Director of the National Institute of Drug Abuse reports, "Every year more than 100,000 people, most of them adolescents, seek treatment for their inability to control their marijuana use." According to the Scottish Drug Misuse Statistics in Scotland 2002,…

Jhaveri, Sujata

2005-01-01

152

Cannabis cue-induced brain activation correlates with drug craving in limbic and visual salience regions: preliminary results.  

PubMed

Craving is a major motivator underlying drug use and relapse but the neural correlates of cannabis craving are not well understood. This study sought to determine whether visual cannabis cues increase cannabis craving and whether cue-induced craving is associated with regional brain activation in cannabis-dependent individuals. Cannabis craving was assessed in 16 cannabis-dependent adult volunteers while they viewed cannabis cues during a functional MRI (fMRI) scan. The Marijuana Craving Questionnaire was administered immediately before and after each of three cannabis cue-exposure fMRI runs. FMRI blood-oxygenation-level-dependent (BOLD) signal intensity was determined in regions activated by cannabis cues to examine the relationship of regional brain activation to cannabis craving. Craving scores increased significantly following exposure to visual cannabis cues. Visual cues activated multiple brain regions, including inferior orbital frontal cortex, posterior cingulate gyrus, parahippocampal gyrus, hippocampus, amygdala, superior temporal pole, and occipital cortex. Craving scores at baseline and at the end of all three runs were significantly correlated with brain activation during the first fMRI run only, in the limbic system (including amygdala and hippocampus) and paralimbic system (superior temporal pole), and visual regions (occipital cortex). Cannabis cues increased craving in cannabis-dependent individuals and this increase was associated with activation in the limbic, paralimbic, and visual systems during the first fMRI run, but not subsequent fMRI runs. These results suggest that these regions may mediate visually cued aspects of drug craving. This study provides preliminary evidence for the neural basis of cue-induced cannabis craving and suggests possible neural targets for interventions targeted at treating cannabis dependence. PMID:24035535

Charboneau, Evonne J; Dietrich, Mary S; Park, Sohee; Cao, Aize; Watkins, Tristan J; Blackford, Jennifer U; Benningfield, Margaret M; Martin, Peter R; Buchowski, Maciej S; Cowan, Ronald L

2013-11-30

153

Marijuana Neurobiology and Treatment  

ERIC Educational Resources Information Center

Marijuana is the number one illicit drug of abuse worldwide and a major public health problem, especially in the younger population. The objective of this article is to update and review the state of the science and treatments available for marijuana dependence based on a pre-meeting workshop that was presented at ISAM 2006. At the workshop,…

Elkashef, Ahmed; Vocci, Frank; Huestis, Marilyn; Haney, Margaret; Budney, Alan; Gruber, Amanda; el-Guebaly, Nady

2008-01-01

154

Marijuana and Tobacco  

Microsoft Academic Search

Smoking among teens and college students is a significant public health challenge. Tobacco, marijuana, and alcohol continue to be the most commonly abused drugs by teens and young adults. Educational efforts have resulted in increased awareness of the mortality and morbidity attributed to smoking, second-hand smoke, and prenatal exposure to tobacco. Short- and long-term consequences of marijuana use are well

Laura Michelle Tullis; Robert Dupont; Kimberly Frost-Pineda; Mark S. Gold

2003-01-01

155

Marijuana Neurobiology and Treatment  

Microsoft Academic Search

Marijuana is the number one illicit drug of abuse worldwide and a major public health problem, especially in the younger population. The objective of this article is to update and review the state of the science and treatments available for marijuana dependence based on a pre-meeting workshop that was presented at ISAM 2006. At the workshop, several papers were presented

Ahmed Elkashef; Frank Vocci; Marilyn Huestis; Margaret Haney; Alan Budney; Amanda Gruber; Nady el-Guebaly

2008-01-01

156

Electrophysiological evidence of early attentional bias to drug-related pictures in chronic cannabis users.  

PubMed

Behavioral and electrophysiological correlates of attentional bias to cannabis-related cues were investigated in a marijuana dependent group and a non-user group employing a drug Stroop task in which cannabis-related, negative and neutral images were presented. Behaviorally, cannabis users were less accurate during drug-containing blocks than non-users. Electrophysiologically, in chronic marijuana-users, an early positive ERP enhancement over left frontal scalp (EAP, 200-350ms) was present in response to drug-containing blocks relative to negative blocks. This effect was absent in the non-user group. Furthermore, drug-containing blocks gave rise to enhanced voltage of a posterior P300 (300-400ms), and a posterior sustained slow wave (LPP, 400-700ms) relative to negative blocks. However, such effects were similar between cannabis users and non-users. Brain source imaging in cannabis users revealed a generator for the EAP effect to drug stimuli in left ventromedial prefrontal cortex/medial orbitofrontal cortex, a region active in fMRI studies of drug cue-reactivity and a target of the core dopaminergic mesolimbic pathway involved in the processing of substances of abuse. This study identifies the timing and brain localization of an ERP correlate of early attentional capture to drug-related pictures in chronic marijuana users. The EAP to drug cues may identify a new electrophysiological marker with clinical implications for predicting abstinence versus relapse or to evaluate treatment interventions. PMID:24126204

Asmaro, Deyar; Carolan, Patrick L; Liotti, Mario

2014-01-01

157

Structural organization of the nuclear ribosomal RNA genes in Cannabis and Humulus (Cannabaceae)  

Microsoft Academic Search

The structural organization of the nuclear ribosomal DNA (rDNA) of Humulus lupulus, H. japonicus and Cannabis sativa was determined by restriction site mapping. A high degree of DNA sequence similarity was evident in the coding regions of\\u000a the rDNA repeats of the taxa and supports the placement of Cannabis and Humulus in one family, Cannabaceae. However, the presence of a

M. Pillay; S. T. Kenny

2006-01-01

158

Marijuana use and mortality.  

PubMed Central

OBJECTIVES: The purpose of this study was to examine the relationship of marijuana use to mortality. METHODS: The study population comprised 65171 Kaiser Permanente Medical Care Program enrollees, aged 15 through 49 years, who completed questionnaires about smoking habits, including marijuana use, between 1979 and 1985. Mortality follow-up was conducted through 1991. RESULTS: Compared with nonuse or experimentation (lifetime use six or fewer times), current marijuana use was not associated with a significantly increased risk of non-acquired immunodeficiency syndrome (AIDS) mortality in men (relative risk [RR] = 1.12, 95% confidence interval [CI] = 0.89, 1.39) or of total mortality in women (RR = 1.09, 95% CI = 0.80, 1.48). Current marijuana use was associated with increased risk of AIDS mortality in men (RR = 1.90, 95% CI = 1.33, 2.73), an association that probably was not causal but most likely represented uncontrolled confounding by male homosexual behavior. This interpretation was supported by the lack of association of marijuana use with AIDS mortality in men from a Kaiser Permanente AIDS database. Relative risks for ever use of marijuana were similar. CONCLUSIONS: Marijuana use in a prepaid health care-based study cohort had little effect on non-AIDS mortality in men and on total mortality in women. PMID:9146436

Sidney, S; Beck, J E; Tekawa, I S; Quesenberry, C P; Friedman, G D

1997-01-01

159

Impulsivity, Variation in the Cannabinoid Receptor (CNR1) and Fatty Acid Amide Hydrolase (FAAH) Genes, and Marijuana-Related Problems  

PubMed Central

Objective: Impulsivity is associated with increased marijuana use and subsequent marijuana-related problems among marijuana users. In addition, single nucleotide polymorphisms (SNPs) in the cannabinoid receptor 1 (CNR1) and fatty acid amide hydrolase (FAAH) genes have been associated with cannabis-related phenotypes. This exploratory study tested whether the association between different aspects of impulsivity and the number of marijuana-related problems among users is explicated by variation in these putative cannabinoid-related genes. Method: A total of 151 young adult regular marijuana users (used on M = 41.4% of the prior 60 days, SD = 24.3%) provided DNA and completed measures of trait (Barratt Impulsiveness Scale) and behavioral impulsivity (Stop Signal Task and Delay Discounting Questionnaire), as well as a self-report of marijuana-related problems. Three CNR1 and five FAAH SNPs were genotyped, tested for haplotype blocks, and subsequently examined for association with phenotypes described above. Results: CNR1 variation significantly moderated the association between trait-level, but not behavioral, impulsivity and marijuana-related problems, such that the combination of higher trait impulsivity and CNR1 variation was associated with a greater number of marijuana-related problems. In contrast, there were no significant FAAH by impulsivity interactions; however, there was a main effect of FAAH on marijuana-related problems. Conclusions: These findings support an association with CNR1 and FAAH genes and marijuana-related problems among regular marijuana users. CNR1 variation emerged as a moderator of the relationship between trait impulsivity and marijuana problems, thus suggesting that marijuana users with CNR1 risk variants and a higher trait impulsivity are at greater risk for developing marijuana-related problems and supporting a role for CNR1 in a broader impulsivity phenotype. PMID:24172113

Bidwell, L. Cinnamon; Metrik, Jane; McGeary, John; Palmer, Rohan H. C.; Francazio, S.; Knopik, Valerie S.

2013-01-01

160

Effects of Cannabis on Impulsivity: A Systematic Review of Neuroimaging Findings  

PubMed Central

We conducted a systematic review to assess the evidence for specific effects of cannabis on impulsivity, disinhibition and motor control. The review had a specific focus on neuroimaging findings associated with acute and chronic use of the drug and covers literature published up until May 2012. Seventeen studies were identified, of which 13 met the inclusion criteria; three studies investigated acute effects of cannabis (1 fMRI, 2 PET), while six studies investigated non-acute functional effects (4 fMRI, 2 PET), and four studies investigated structural alterations. Functional imaging studies of impulsivity studies suggest that prefrontal blood flow is lower in chronic cannabis users than in controls. Studies of acute administration of THC or marijuana report increased brain metabolism in several brain regions during impulsivity tasks. Structural imaging studies of cannabis users found differences in reduced prefrontal volumes and white matter integrity that might mediate the abnormal impulsivity and mood observed in marijuana users. To address the question whether impulsivity as a trait precedes cannabis consumption or whether cannabis aggravates impulsivity and discontinuation of usage more longitudinal study designs are warranted. PMID:23829358

Wrege, Johannes; Schmidt, Andre; Walter, Anna; Smieskova, Renata; Bendfeldt, Kerstin; Radue, Ernst-Wilhelm; Lang, Undine E.; Borgwardt, Stefan

2014-01-01

161

Comorbidity: cannabis and complexity.  

PubMed

Cannabis is one of the most commonly used illicit drugs, and its effects have traditionally been seen as less harmful than outcomes associated with the highly prevalent use of alcohol and other illicit substances (e.g., cocaine and amphetamines), and injecting drugs. Consequently, less attention has been focused on developing and evaluating interventions in this area. However, current research supports the idea that cannabis does pose a number of acute and chronic health risks to the individual and to society. The authors review findings concerning the physiological and neurological effects of cannabis, prevalence of use, and studies concerning its possible role as a "gateway" drug. Diagnostic criteria for cannabis dependence and abuse are discussed, with a focus on whether a cannabis withdrawal syndrome exists and if so how it can be diagnosed. There is strong support for a link between cannabis and the development and exacerbation of psychosis and other mental health conditions (e.g., anxiety, depression). Further research is needed to determine the underlying neurochemical processes and their possible contribution to etiology, as well as the social factors that contribute to the increasing use of cannabis by young people. In addition there is a need for systematic evaluation using randomized controlled trials to determine effective prevention and treatment strategies. A number of public health programs that address cannabis use are reviewed along with available evidence for their effectiveness. PMID:15920390

Raphael, Beverley; Wooding, Sally; Stevens, Garry; Connor, Jason

2005-05-01

162

CANNABIS CLINIC Fusarium Wilt  

Microsoft Academic Search

Fusarium wilt is caused by two closely-related fungi, Fusarium oxysporum f. sp. vasinfectum and Fusarium oxysporum f. sp. cannabis. The disease was first described on hemp in Eastern Europe about 50 years ago, but is now found throughout the Northern hemisphere. Greenhouse studies demonstrated that all cultivars of Cannabis that were tested are susceptible. Signs and symptoms, life history of

John M. McPartland; Karl W. Hillig

2004-01-01

163

Creating the cannabis user  

Microsoft Academic Search

In January 2004 the British government announced that cannabis would be reclassified from Classes B to C, taking into account its level of harmfulness for human health and considering the penalties for possession and supplying. It was argued by the Government, that cannabis reclassification would save some resources and stop the criminalisation of otherwise law-abiding citizens. One year later, in

Beatriz Acevedo

2007-01-01

164

Cannabis Use and Mental Health  

Microsoft Academic Search

This paper investigates whether cannabis use leads to worse mental health. To do so, we account for common unobserved factors aecting mental health and cannabis consumption by modeling mental health jointly with the dy- namics of cannabis use. Our main finding is that using cannabis increases the likelihood of mental health problems, with current use having a larger eect than

Carol Propper; Tue Gørgens; Chikako Yamauchi

165

Accommodating the medical use of marijuana: surveying the differing legal approaches in Australia, the United States and Canada.  

PubMed

While the scientific and medical communities continue to be divided on the therapeutic benefits and risks of cannabis use, anecdotal evidence from medical users themselves suggests that using cannabis is indeed improving their quality of life by alleviating their pain and discomfort. Notwithstanding the benefits anecdotally claimed by these medical users and the existence of some scientific studies confirming their claims, criminal drug laws in all Australian and most United States jurisdictions continue to prohibit the possession, cultivation and supply of cannabis even for medical purposes. However, in contrast to Australia and most parts of the United States, the medical use of cannabis has been legal in Canada for about a decade. This article reviews these differing legal and regulatory approaches to accommodating the medical use of cannabis (namely, marijuana) as well as some of the challenges involved in legalising it for medical purposes. PMID:20329455

Bogdanoski, Tony

2010-02-01

166

Depersonalization after marijuana smoking.  

PubMed

Depersonalization and other behavioral and physiological indices were monitored before and after the administration of high- and low-potency marijuana cigarettes and a placebo cigarette in 35 physically and mentally healthy normal volunteers. The cigarettes were administered under double-blind conditions during three visits to the laboratory separated by a minimum of 1 week. Marijuana smoking, but not placebo smoking, was associated with significant depersonalization that was maximal 30 min after smoking the high-potency cigarettes. Other behavioral changes induced by marijuana included disintegration of time sense, sensation of "high," increased state anxiety, tension, anger, and confusion. Respiration, pulse rate, and systolic blood pressure also increased after marijuana smoking. Multiple regression identified temporal disintegration as the most significant predictor of depersonalization. PMID:8490070

Mathew, R J; Wilson, W H; Humphreys, D; Lowe, J V; Weithe, K E

1993-03-15

167

Cannabis dependence, cognitive control and attentional bias for cannabis words.  

PubMed

One of the characteristics of people suffering from addictive behaviors is the tendency to be distracted by drug cues. This attentional bias for drug cues is thought to lead to increased craving and drug use, and may draw individuals into a vicious cycle of drug addiction. In the current study we developed a Dutch version of the cannabis Stroop task and measured attentional bias for cannabis words in a group of heavy cannabis users and matched controls. The classical Stroop task was used as a global measure of cognitive control and we examined the relationship between cognitive control, cannabis-related problems, cannabis craving and cannabis attentional bias. Using our version of the cannabis Stroop task, a group of heavy cannabis users showed attentional bias to cannabis words, whereas a control group of non-users did not. Furthermore, within the group of cannabis users, those who were clinically recognized as dependent showed a stronger attentional bias than the heavy, non-dependent users. Cannabis users who displayed reduced cognitive control (as measured with the classical Stroop task) showed increased session-induced craving. Contrary to expectations, however, cognitive control did not appear to modulate the relationship between attentional bias to cannabis words (cannabis Stroop task) and cannabis dependence. This study confirmed the relationship between cannabis dependence and attentional bias and extends this by highlighting a moderating role for cognitive control, which may make some more vulnerable to craving. PMID:24018225

Cousijn, J; Watson, P; Koenders, L; Vingerhoets, W A M; Goudriaan, A E; Wiers, R W

2013-12-01

168

Opioid antagonism enhances marijuana's effects in heavy marijuana smokers  

PubMed Central

Rationale and objective Studies in laboratory animals strongly suggest reciprocal modulation of the opioidergic and endocannabinoid systems, a relationship that has not been demonstrated in humans. This study sought to clarify this interaction by assessing how a range of naltrexone doses altered the subjective, cognitive, and cardiovascular effects of marijuana. Material and methods Daily marijuana smokers (n=29) participated in this within-subject, randomized, double-blind, placebo-controlled study. Naltrexone (0, 12, 25, 50, or 100 mg) was administered before active or inactive marijuana (3.27 or 0% THC) was smoked. Results Active marijuana increased subjective ratings of marijuana ‘Strength,’ ‘High,’ and positive subjective ratings of marijuana quality and drug effect including ‘Liking,’ ‘Good,’ and ‘Take Again’ compared to inactive marijuana. Naltrexone alone decreased ratings of ‘Liking,’ ‘Take Again,’ and ‘Stimulated’ compared with placebo, but increased ratings of drug ‘Strength,’ ‘High,’ ‘Good,’ ‘Liking,’ ‘Stimulated,’ and ‘Take Again’ when administered under active marijuana conditions. Active marijuana did not affect performance on cognitive tasks relative to inactive marijuana, whereas naltrexone decreased performance when administered alone or in combination with active marijuana. Active marijuana increased heart rate compared to inactive marijuana under placebo naltrexone conditions. Although naltrexone alone decreased heart rate, it further increased marijuana's cardiovascular effect. Conclusions In heavy marijuana smokers opioid-receptor blockade enhanced the subjective and cardiovascular effects of marijuana, suggesting that endogenous opioids dampen cannabinoid effects in this population. These findings demonstrate that a broad range of clinically used doses of naltrexone potentially increases the abuse liability and cardiovascular risks of cannabinoids. PMID:20490465

Haney, Margaret

2010-01-01

169

Does Marijuana Help Treat Glaucoma?  

MedlinePLUS

... Screening Guidelines Home Remedies for Simple Eye Problems Medical Marijuana for Glaucoma Pregnancy Preventing Eye Injuries Smokers Sports ... in vision may start to occur. Follow Us Medical marijuana is promoted as a treatment for many diseases, ...

170

Smoking Marijuana and the Lungs  

MedlinePLUS

... the immune system. Aspergillus is present in our environment including our home (the dust in carpets, air ducts etc.). Aspergillus can live on the marijuana plant and be inhaled in the marijuana smoke. It ...

171

An examination of opinions toward marijuana policies among high school seniors in the United States.  

PubMed

Abstract Support for marijuana (cannabis) legalization is increasing in the US, and state-level marijuana policies are rapidly changing. Research is needed to examine correlates of opinions toward legalization among adolescents approaching adulthood as they are at high risk for use. Data were examined from a national representative sample of high school seniors in the Monitoring the Future study (years 2007-2011; N = 11,594) to delineate correlates of opinions toward legalization. A third of students felt marijuana should be entirely legal and 28.5% felt it should be treated as a minor violation; 48.0% felt that if legal to sell it should be sold to adults only, and 10.4% felt it should be sold to anyone. Females, conservatives, religious students, and those with friends who disapprove of marijuana use tended to be at lower odds for supporting legalization, and Black, liberal, and urban students were at higher odds for supporting more liberal policies. Recent and frequent marijuana use strongly increased odds for support for legalization; however, 16.7% of non-lifetime marijuana users also reported support for legalization. Findings should be interpreted with caution as state-level data were not available, but results suggest that support for marijuana legalization is common among specific subgroups of adolescents. PMID:25364985

Palamar, Joseph J

2014-01-01

172

Is Marijuana a Gateway Drug?  

Microsoft Academic Search

Although many cocaine users initiated marijuana prior to cocaine, no formal evidence exists that marijuana consumption causes, or is a gateway to, cocaine consumption. This paper employs a two-stage instrumental variable procedure to estimate a structural effect of past marijuana demand on current cocaine demand using data from the National Longitudinal Survey of Youth. Extensive specification testing verifies that the

Jeffrey DeSimone

1998-01-01

173

THREE FACTS ABOUT MARIJUANA PRICES  

Microsoft Academic Search

Australians are among the largest consumers of marijuana in the world, and estimates show that their expenditure on marijuana is about twice that on wine. In this paper we analyse the evolution of marijuana prices in Australia and show that they have declined in real terms by almost 40 percent over the last decade. This decline is far above that

Kenneth W. Clements

2003-01-01

174

Three Facts About Marijuana Prices  

Microsoft Academic Search

Australians are among the largest consumers of marijuana in the world, and estimates show that their expenditure on marijuana is about twice that on wine. In this paper we analyse the evolution of marijuana prices in Australia and show that they have declined in real terms by almost 40 percent over the decade. This decline is far above that experienced

Kenneth W. Clements

2002-01-01

175

Cannabis and educational achievement  

Microsoft Academic Search

Aims To examine the relationship between cannabis use in adolescence\\/young adulthood and levels of educational attainment. Design Data were gathered over the course of a 25-year longitudinal study of a birth cohort of 1265 New Zealand children. Measurements Measures analysed included (a) frequency of cannabis use in adolescence and young adulthood (15-25 years); (b) levels of educational achievement to age

David M. Fergusson; L. John Horwood; Annette L. Beautrais

2003-01-01

176

Is recent cannabis use associated with acute coronary syndromes? An illustrative case series.  

PubMed

Cannabis is a frequently used recreational drug that potentially imposes serious health problems. We report three cases where recent and/or chronic use of marijuana led to severe cardiac dysfunction. All three patients collapsed at home and required cardiopulmonary resuscitation (CPR) with initial restoration of spontaneous circulation (ROSC). The mechanism of the cardiovascular collapse was different in each case. The first case presented with asystole and was found to have diffuse coronary vasospasm on coronary angiography in the hours after acute cannabis abuse. In the second case, an acute anterior infarction with occlusion of both the right coronary artery (RCA) and the left anterior descendens (LAD) was observed in a young patient without known cardiovascular risks but with chronic cannabis abuse. The third case presented at home with ventricular fibrillation presumably caused by an acute coronary syndrome due to left anterior descending (LAD) artery occlusion. The hetero-anamnesis of the family reported that all three patients had recently used cannabis. Toxicological screening also showed no other substance abuse than cannabis. Using these three cases, we would like to illustrate that the widespread use of cannabis is not as innocent as is believed. Cannabis use can lead to severe cardiovascular problems and sudden death, not only in people at increased cardiovascular risk, but also in young people without any medical history or risk factors. PMID:24783463

Casier, Isabelle; Vanduynhoven, Philippe; Haine, Steven; Vrints, Chris; Jorens, Philippe G

2014-04-01

177

Cigarette smoking during an N-acetylcysteine-assisted cannabis cessation trial in adolescents  

PubMed Central

Background and Objectives Tobacco and cannabis use are both highly prevalent worldwide. Their co-use is also common in adults and adolescents. Despite this frequent co-occurrence, cessation from both substances is rarely addressed in randomized clinical trials. Given evidence that tobacco use may increase during cannabis cessation attempts, and additionally that tobacco users have poorer cannabis cessation outcomes, we explored tobacco outcomes, specifically cigarette smoking, from an adolescent cannabis cessation trial that tested the efficacy of N-acetylesteine (NAC). Methods Cannabis-dependent adolescents (ages 15–21; n=116) interested in cannabis treatment were randomized to NAC (1200 mg bid) or matched placebo for 8 weeks. Participants did not need to be cigarette smokers or be interested in smoking cessation to qualify for inclusion. Results Approximately 59% of enrolled participants were daily and non-daily cigarette smokers, and only differed from non-smoking participants on the compulsion sub-scale of the Marijuana Craving Questionnaire. Among cigarette smokers who were retained in the study, there was no change in cigarettes per day for either NAC or placebo groups during the 8-week treatment phase. Being a cigarette smoker did not appear to influence the effects of NAC on cannabis abstinence, though there was a trend in the placebo group of poorer cannabis outcomes for cigarette smokers vs. non-smokers. Conclusions No evidence was found of compensatory cigarette smoking during this cannabis cessation trial in adolescents. Further work assessing interventions to reduce both cannabis and tobacco use in this population is greatly needed. PMID:24720376

McClure, Erin A.; Baker, Nathaniel L.; Gray, Kevin M.

2014-01-01

178

Marijuana craving trajectories in an adolescent marijuana cessation pharmacotherapy trial.  

PubMed

Marijuana is the most widely used illicit substance among youths and recent epidemiological data indicate that rates of marijuana use are on the rise. The purpose of this study was to examine marijuana craving trajectories among adolescents in an eight-week, placebo-controlled pharmacotherapy trial targeting marijuana cessation. All participants received contingency management and cessation counseling, and were randomized to either N-acetylcysteine (1200mg NAC twice daily; n=45) or placebo (n=44). Craving for marijuana was measured using the short-form of the Marijuana Craving Questionnaire (MCQ). Results demonstrated a significant decrease in MCQ scores over time for the total sample, but no significant differential change in scores between the NAC and placebo groups. This lack of significant difference is in the setting of NAC participants submitting significantly more negative urine cannabinoid tests as compared to placebo participants. This suggests that cessation effects associated with NAC may be mediated by effects other than marijuana craving. PMID:23261493

Roten, Amanda T; Baker, Nathaniel L; Gray, Kevin M

2013-03-01

179

Medical Marijuana in Certain Neurological Disorders  

MedlinePLUS

... of Systematic Review for PATIENTS and their FAMILIES MEDICAL MARIJUANA IN CERTAIN NEUROLOGICAL DISORDERS ©2014 American Academy of ... systematic review, visit AAN.com/guidelines. What is medical marijuana? Marijuana is an herb that grows naturally in ...

180

Chronic Marijuana Use and The Brain  

MedlinePLUS Videos and Cool Tools

... lower right-hand corner of the player. Chronic Marijuana Use and The Brain HealthDay November 11, 2014 Related MedlinePlus Pages Brain Diseases Marijuana Transcript Long-term marijuana use may lead to ...

181

Pharmacology and toxicology of Cannabis derivatives and endocannabinoid agonists.  

PubMed

For centuries Cannabis sativa and cannabis extracts have been used in natural medicine. Delta(9)-tetrahydrocannabinol (THC) is the main active ingredient of Cannabis. THC seems to be responsible for most of the pharmacological and therapeutic actions of cannabis. In a few countries THC extracts (i.e. Sativex) or THC derivatives such as nabilone, and dronabinol are used in the clinic for the treatment of several pathological conditions like chemotherapy-induced nausea and vomiting, multiple sclerosis and glaucoma. On the other hand the severe side effects and the high abuse liability of these agents represent a serious limitation in their medical use. In addition, diversion in the use of these active ingredients for recreational purpose is a concern. Over recent years, alternative approaches using synthetic cannabinoid receptor agonists or agents acting as activators of the endocannabinoid systems are under scrutiny with the hope to develop more effective and safer clinical applications. Likely, in the near future few of these new molecules will be available for clinical use. The present article review recent study and patents with focus on the cannabinoid system as a target for the treatment of central nervous system disorders with emphasis on agonists. PMID:19832688

Gerra, Gilberto; Zaimovic, Amir; Gerra, Maria L; Ciccocioppo, Roberto; Cippitelli, Andrea; Serpelloni, Giovanni; Somaini, Lorenzo

2010-01-01

182

Characteristics of cannabinoids composition of Cannabis plants grown in Northern Thailand and its forensic application.  

PubMed

The Thai government has recognized the possibility for legitimate cultivation of hemp. Further study of certain cannabinoid characteristics is necessary in establishing criteria for regulation of cannabis cultivation in Thailand. For this purpose, factors affecting characteristics of cannabinoids composition of Thai-grown cannabis were investigated. Plants were cultivated from seeds derived from the previous studies under the same conditions. 372 cannabis samples from landraces, three different trial fields and seized marijuana were collected. 100g of each sample was dried, ground and quantitatively analyzed for THC, CBD and CBN contents by GC-FID. The results showed that cannabis grown during March-June which had longer vegetative stages and longer photoperiod exposure, had higher cannabinoids contents than those grown in August. The male plants grown in trial fields had the range of THC contents from 0.722% to 0.848% d.w. and average THC/CBD ratio of 1.9. Cannabis in landraces at traditional harvest time of 75 days had a range of THC contents from 0.874% to 1.480% d.w. and an average THC/CBD ratio of 2.6. The THC contents and THC/CBD ratios of cannabis in second generation crops grown in the same growing season were found to be lower than those grown in the first generation, unless fairly high temperatures and a lesser amount of rainfall were present. The average THC content in seized fresh marijuana was 2.068% d.w. while THC/CBD ratios were between 12.6 and 84.09, which is 10-45 times greater than those of similar studied cannabis samples from the previous study. However, most Thai cannabis in landraces and in trial fields giving a low log(10) value of THC/CBD ratio at below 1 may be classified as intermediate type, whereas seized marijuana giving a higher log(10) value at above 1 could be classified as drug type. Therefore, the expanded information provided by the current study will assist in the development of criteria for regulation of hemp cultivation in Thailand. PMID:21636228

Tipparat, Prapatsorn; Natakankitkul, Surapol; Chamnivikaipong, Pipop; Chutiwat, Sirot

2012-02-10

183

Extraction of high quality DNA from seized Moroccan cannabis resin (Hashish).  

PubMed

The extraction and purification of nucleic acids is the first step in most molecular biology analysis techniques. The objective of this work is to obtain highly purified nucleic acids derived from Cannabis sativa resin seizure in order to conduct a DNA typing method for the individualization of cannabis resin samples. To obtain highly purified nucleic acids from cannabis resin (Hashish) free from contaminants that cause inhibition of PCR reaction, we have tested two protocols: the CTAB protocol of Wagner and a CTAB protocol described by Somma (2004) adapted for difficult matrix. We obtained high quality genomic DNA from 8 cannabis resin seizures using the adapted protocol. DNA extracted by the Wagner CTAB protocol failed to give polymerase chain reaction (PCR) amplification of tetrahydrocannabinolic acid (THCA) synthase coding gene. However, the extracted DNA by the second protocol permits amplification of THCA synthase coding gene using different sets of primers as assessed by PCR. We describe here for the first time the possibility of DNA extraction from (Hashish) resin derived from Cannabis sativa. This allows the use of DNA molecular tests under special forensic circumstances. PMID:24124454

El Alaoui, Moulay Abdelaziz; Melloul, Marouane; Alaoui Amine, Sanaâ; Stambouli, Hamid; El Bouri, Aziz; Soulaymani, Abdelmajid; El Fahime, Elmostafa

2013-01-01

184

Marijuana Is Far From "Harmless."  

ERIC Educational Resources Information Center

Citing harmful physiological effects of marijuana, the author asserts that it is the single most serious new threat to our nation's health. He urges parents and school personnel to learn about marijuana and take a strong stand against it. (Condensed from "PTA Today," May 1981, p3-5.) (Author/SJL)

DuPont, Robert L.

1981-01-01

185

Decreased depression in marijuana users  

Microsoft Academic Search

Over 4400 adult internet users completed The Center for Epidemiologic Studies Depression scale and measures of marijuana use. We employed an internet survey in an effort to recruit the most depressed and marijuana-involved participants, including those who might prove unwilling to travel to the laboratory or discuss drug use on the phone or in person. We compared those who consumed

Thomas F. Denson; Mitchell Earleywine

2006-01-01

186

Medicinal Marijuana: A Comprehensive Review  

Microsoft Academic Search

Considerable controversy exists regarding the role of marijuana as a therapeutic agent; however, many practitioners are taught very little about existing marijuana data. The authors therefore undertook a comprehensive literature review of the topic. References were identified using textbo oks, review and opinion articles, and a primary literature review in MEDLINE. Sources were included in this review based primarily on

R. Jan Gurley; Richard Aranow; Mitchell Katz

1998-01-01

187

Cannabis and schizophrenia  

PubMed Central

Background Many people with schizophrenia use cannabis and its effects on the illness are unclear. Objectives To evaluate the effects of cannabis use on people with schizophrenia and schizophrenia-like illnesses. Search methods We searched the Cochrane Schizophrenia Group Trials Register (April 2007) which is based on regular searches of BIOSIS, CENTRAL, CINAHL, EMBASE, MEDLINE and PsycINFO. Selection criteria We included all randomised trials involving cannabinoids and people with schizophrenia or schizophrenia-like illnesses. Data collection and analysis We extracted data independently. For dichotomous data we calculated relative risks (RR) and their 95% confidence intervals (CI) on an intention-to-treat basis, based on a fixed effects model. We calculated the numbers needed to treat/harm (NNT/NNH). For continuous data, we calculated weighted mean differences (WMD) again based on a fixed effects model. Main results We identified one randomised trial. No significant differences were found between the Cannabis and Psychosis Therapy (CAP) intervention group and the Psychoeducaton (PE) intervention for use of cannabis at three months assessment (n=47, RR 1.04 CI 0.6 to 1.7). BPRS-extended scale scores at three months assessment (n=47, WMD ?3.60 CI ?12.8 to 5.6) and nine months assessment (n=47, WMD 0.80 CI ?7.5 to 9.1) were non-significant between CAP and PE. We found no significant improvement in social functioning in the CAP group compared with PE (at 3 months, n=47, WMD ?0.80 CI ?10 to 8.4) and (at 9 months, n=47, WMD ?4.70 CI ?14.5 to 5.1). Authors’ conclusions At present, there is insufficient evidence to support or refute the use of cannabis/cannabinoid compounds for people suffering with schizophrenia. This review highlights the need for well designed, conducted and reported clinical trials to address the potential effects of cannabis based compounds for people with schizophrenia. PMID:18646115

Rathbone, John; Variend, Hannele; Mehta, Hetal

2014-01-01

188

Initiation into adolescent marijuana use.  

PubMed

In this longitudinal study, the relationship of three domains (personality/attitudinal orientations, peer relationships, and family socialization factors) with initiation into adolescent marijuana use was examined. One hundred and eighty-three adolescent boys and girls and their mothers were interviewed when the adolescents were 13-17 years old and again three years later. The results indicate that the domains of personality and family (with control on the other two domains and demographic variables) each appear to be related to subsequent involvement with marijuana. In contrast, the peer domain is not significantly associated with initiation into marijuana use once personality, family, and demographic clusters are controlled. However, the interaction of maternal demographic clusters are controlled. However, the interaction of maternal conventionality and peer marijuana use was related to initiation into marijuana use. PMID:6968818

Brook, J S; Lukoff, I F; Whiteman, M

1980-09-01

189

Medical marijuana in neurology.  

PubMed

Constituents of the Cannabis plant, cannabinoids, may be of therapeutic value in neurologic diseases. The most abundant cannabinoids are ?(9)-tetrahydrocannabinol, which possesses psychoactive properties, and cannabidiol, which has no intrinsic psychoactive effects, but exhibits neuroprotective properties in preclinical studies. A small number of high-quality clinical trials support the safety and efficacy of cannabinoids for treatment of spasticity of multiple sclerosis, pain refractory to opioids, glaucoma, nausea and vomiting. Lower level clinical evidence indicates that cannabinoids may be useful for dystonia, tics, tremors, epilepsy, migraine and weight loss. Data are also limited in regards to adverse events and safety. Common nonspecific adverse events are similar to those of other CNS 'depressants' and include weakness, mood changes and dizziness. Cannabinoids can have cardiovascular adverse events and, when smoked chronically, may affect pulmonary function. Fatalities are rare even with recreational use. There is a concern about psychological dependence, but physical dependence is less well documented. Cannabis preparations may presently offer an option for compassionate use in severe neurologic diseases, but at this point, only when standard-of-care therapy is ineffective. As more high-quality clinical data are gathered, the therapeutic application of cannabinoids will likely expand. PMID:25427150

Benbadis, Selim R; Sanchez-Ramos, Juan; Bozorg, Ali; Giarratano, Melissa; Kalidas, Kavita; Katzin, Lara; Robertson, Derrick; Vu, Tuan; Smith, Amanda; Zesiewicz, Theresa

2014-12-01

190

Cannabis and the brain  

Microsoft Academic Search

Summary The active compound in herbal cannabis, D9-tetrahydro- cannabinol, exerts all of its known central effects through the CB1 cannabinoid receptor. Research on cannabinoid mechanisms has been facilitated by the availability of selective antagonists acting at CB1 recep- tors and the generation of CB1 receptor knockout mice. Particularly important classes of neurons that express high levels of CB1 receptors are

Leslie Iversen

2003-01-01

191

Marijuana Motives: Young Adults’ Reasons for Using Marijuana  

PubMed Central

Previous research has evaluated marijuana motives among adolescents and emerging adults using a predetermined set of motives, largely adapted from the alcohol literature. This research was designed to identify marijuana motives from the perspective of the user. Recent high school graduates who reported using marijuana (N = 634) provided self-generated reasons for using. The most frequently reported reasons included enjoyment/fun, conformity, experimentation, social enhancement, boredom, and relaxation. Regression analyses revealed that experimentation was consistently associated with less use and fewer problems whereas enjoyment, habit, activity enhancement, and altered perception or perspectives were associated with heavier use and more problems. PMID:17097817

Lee, Christine M.; Neighbors, Clayton; Woods, Briana A.

2009-01-01

192

Medicinal marijuana: a comprehensive review.  

PubMed

Considerable controversy exists regarding the role of marijuana as a therapeutic agent; however, many practitioners are taught very little about existing marijuana data. The authors therefore undertook a comprehensive literature review of the topic. References were identified using textbooks, review and opinion articles, and a primary literature review in MEDLINE. Sources were included in this review based primarily on the quality of the data. Some data exists that lends credence to many of the claims about marijuana's properties. In general, however, the body of literature about marijuana is extremely poor in quality. Marijuana and/or its components may help alleviate suffering in patients with a variety of serious illnesses. Health care providers can best minimize short term adverse consequences and drug interactions for terminally ill patients by having a thorough understanding of the pharmacology of marijuana, potential adverse reactions, infection risks, and drug interactions (along with on-going monitoring of the patient). For chronic conditions, the significance and risk of short and long term adverse effects must be weighed against the desired benefit. Patients who are best suited to medicinal marijuana will be those who will gain substantial benefit to offset these risks, and who have failed a well-documented, compliant and comprehensive approach to standard therapies. PMID:9692375

Gurley, R J; Aranow, R; Katz, M

1998-01-01

193

Individual and Additive Effects of the CNR1 and FAAH Genes on Brain Response to Marijuana Cues  

Microsoft Academic Search

As previous work has highlighted the significance of the cannabinoid receptor 1 (CNR1) and fatty acid amide hydrolase (FAAH) genes with respect to cannabis dependence (CD), this study sought to characterize the neural mechanisms that underlie these genetic effects. To this end, we collected DNA samples and fMRI data using a cue-elicited craving paradigm in thirty-seven 3-day-abstinent regular marijuana users.

Francesca M Filbey; Joseph P Schacht; Ursula S Myers; Robert S Chavez; Kent E Hutchison

2010-01-01

194

When Cannabis Is Available and Visible at School--A Multilevel Analysis of Students' Cannabis Use  

ERIC Educational Resources Information Center

Aims: To investigate the links between the visibility of cannabis use in school (measured by teachers' reports of students being under the influence of cannabis on school premises), the proportion of cannabis users in the class, perceived availability of cannabis, as well as adolescent cannabis use. Methods: A multilevel regression model was…

Kuntsche, Emmanuel

2010-01-01

195

Cannabis Use and Mental Health Problems  

Microsoft Academic Search

This paper investigates whether cannabis use leads to worse mental health. To do so, we account for common unobserved factors affecting mental health and cannabis consumption by modeling mental health jointly with the dynamics of cannabis use. Our main finding is that using cannabis increases the likelihood of mental health problems, with current use having a larger effect than past

Jenny Williams

2009-01-01

196

Cannabis Use Is Quantitatively Associated with Nucleus Accumbens and Amygdala Abnormalities in Young Adult Recreational Users  

PubMed Central

Marijuana is the most commonly used illicit drug in the United States, but little is known about its effects on the human brain, particularly on reward/aversion regions implicated in addiction, such as the nucleus accumbens and amygdala. Animal studies show structural changes in brain regions such as the nucleus accumbens after exposure to ?9-tetrahydrocannabinol, but less is known about cannabis use and brain morphometry in these regions in humans. We collected high-resolution MRI scans on young adult recreational marijuana users and nonusing controls and conducted three independent analyses of morphometry in these structures: (1) gray matter density using voxel-based morphometry, (2) volume (total brain and regional volumes), and (3) shape (surface morphometry). Gray matter density analyses revealed greater gray matter density in marijuana users than in control participants in the left nucleus accumbens extending to subcallosal cortex, hypothalamus, sublenticular extended amygdala, and left amygdala, even after controlling for age, sex, alcohol use, and cigarette smoking. Trend-level effects were observed for a volume increase in the left nucleus accumbens only. Significant shape differences were detected in the left nucleus accumbens and right amygdala. The left nucleus accumbens showed salient exposure-dependent alterations across all three measures and an altered multimodal relationship across measures in the marijuana group. These data suggest that marijuana exposure, even in young recreational users, is associated with exposure-dependent alterations of the neural matrix of core reward structures and is consistent with animal studies of changes in dendritic arborization. PMID:24741043

Gilman, Jodi M.; Kuster, John K.; Lee, Sang; Lee, Myung Joo; Kim, Byoung Woo; Makris, Nikos; van der Kouwe, Andre; Blood, Anne J.

2014-01-01

197

Marijuana Usage and Hypnotic Susceptibility  

ERIC Educational Resources Information Center

Anonymous self-reported drug usage data and hypnotic susceptibility scores were obtained from 282 college students. Frequent marijuana users (more than 10 times) showed greater susceptibility to hypnosis than nonusers. (Author)

Franzini, Louis R.; McDonald, Roy D.

1973-01-01

198

Marijuana Use Motives and Social Anxiety among Marijuana Using Young Adults  

PubMed Central

Given the high rates of co-occurring marijuana use and social anxiety, the present investigation examined the relations among marijuana use motives, marijuana use and problems, and social anxiety in 159 (54.7% female) young adults (M age = 18.74, SD = 1.20). As expected, after covarying for a number of variables related to both marijuana use and social anxiety (e.g. gender, alcohol use problems, anxiety sensitivity), social anxiety predicted greater numbers of marijuana use problems. Interestingly, social anxiety was not related to marijuana use frequency. Also consistent with prediction, social anxiety was a significant predictor of coping and conformity motives for marijuana use above and beyond relevant variables. Finally, coping motives for marijuana use mediated the relation between social anxiety and marijuana use problems. These data provide novel evidence for the unique effects of coping-motivated marijuana use in the link between marijuana-related impairment and social anxiety. PMID:17478056

Buckner, Julia D.; Bonn-Miller, Marcel O.; Zvolensky, Michael J.; Schmidt, Norman B.

2007-01-01

199

Characteristics of hemp ( Cannabis sativa L.) seed oil  

Microsoft Academic Search

Characteristics of oil extracted from hempseeds subjected to microwave treatments were evaluated. Microwave treatment improved oil yield, increased carotenoid and other pigment contents and decreased p-anisidine value without significant changes in other properties. Hempseed oil showed absorbance in the UV-B and UV-C ranges with potential for use as a broad spectrum UV protectant. ?-Tocopherol concentrations increased, while the major tocopherol,

B. Dave Oomah; Muriel Busson; David V Godfrey; John C. G Drover

2002-01-01

200

Agronomy of fibre hemp ( Cannabis sativa L.) in Europe  

Microsoft Academic Search

Fibre hemp may yield up to 25 t above ground dry matter per hectare (20 t stem dry matter ha?1) which may contain as much as 12 t ha?1 cellulose, depending on environmental conditions and agronomy. Its performance is affected by the onset of flowering and seed development. Effects of cultivar and management on yield and quality were tested at

P. C. Struik; S. Amaducci; M. J. Bullard; N. C. Stutterheim; G. Venturi; H. T. H. Cromack

2000-01-01

201

(Re)introducing medicinal cannabis.  

PubMed

• After considering extensive scientific and medical evidence, a New South Wales Legislative Council multiparty committee recommended that medicinal cannabis should lawfully be made available for selected-use pharmacotherapy. • The evidence indicates that cannabis has genuine medicinal utility in patients with certain neuropathic conditions, with acceptable levels of risk from mostly mild side effects. • The potential medical benefits of cannabis pharmacotherapy have largely been overlooked, with research and society's attention, in most parts of the world, being directed towards the hazards of its recreational use. • The NSW Government has since dismissed the unanimous and compassionate recommendations of their committee. PMID:24329652

Mather, Laurence E; Rauwendaal, Evert R; Moxham-Hall, Vivienne L; Wodak, Alex D

2013-12-16

202

Cannabis use and suicidal ideation.  

PubMed

Globally, suicide has emerged as the second leading cause of death among youth aged 10-24 years old. In order to better understand the causes of this phenomenon, we investigate the relationship between suicidal ideation and cannabis use. Our empirical analysis is based on a 30-year longitudinal study of a birth cohort. We find that intensive cannabis use - at least several times per week - leads to a higher transition rate into suicidal ideation for males. We find no evidence that suicidal ideation leads to cannabis use for either males or females. PMID:23518573

van Ours, Jan C; Williams, Jenny; Fergusson, David; Horwood, L John

2013-05-01

203

Marijuana effect expectancies: Relations to social anxiety and marijuana use problems  

Microsoft Academic Search

High social anxiety is related to marijuana problems, yet the nature of this relation remains unclear. We examined relations between marijuana effect expectancies, social anxiety, and marijuana among undergraduates (N=337). Social anxiety was related positively to Negative Expectancies and negatively to Tension Reduction Expectancies. Among socially anxious individuals, greater belief that marijuana produces Cognitive and Behavioral Impairment was associated with

Julia D. Buckner; Norman B. Schmidt

2008-01-01

204

Marijuana Use and New Concerns about Medical Marijuana. E-Fact Sheet  

ERIC Educational Resources Information Center

While alcohol remains the drug of choice among college students, marijuana ranks number two with 32 percent reporting using marijuana in 2008. That's a modest decline from 2001, when 36 percent of college students reported marijuana use. While levels of marijuana use by students are determined through a number of national and local surveys, no…

Higher Education Center for Alcohol, Drug Abuse, and Violence Prevention, 2010

2010-01-01

205

Marijuana effect expectancies: relations to social anxiety and marijuana use problems.  

PubMed

High social anxiety is related to marijuana problems, yet the nature of this relation remains unclear. We examined relations between marijuana effect expectancies, social anxiety, and marijuana among undergraduates (N=337). Social anxiety was related positively to Negative Expectancies and negatively to Tension Reduction Expectancies. Among socially anxious individuals, greater belief that marijuana produces Cognitive and Behavioral Impairment was associated with greater marijuana use rates. Negative Expectancies mediated the social anxiety-marijuana problems link. These data provide new insight into problematic marijuana use among this high-risk group. PMID:18694625

Buckner, Julia D; Schmidt, Norman B

2008-11-01

206

Synthetic cannabis and respiratory depression.  

PubMed

In recent years, synthetic cannabis use has been increasing in appeal among adolescents, and its use is now at a 30 year peak among high school seniors. The constituents of synthetic cannabis are difficult to monitor, given the drug's easy accessibility. Currently, 40 U.S. states have banned the distribution and use of some known synthetic cannabinoids, and have included these drugs in the Schedule I category. The depressive respiratory effect in humans caused by synthetic cannabis inhalation has not been thoroughly investigated in the medical literature. We are the first to report, to our knowledge, two cases of self-reported synthetic cannabis use leading to respiratory depression and necessary intubation. PMID:23234589

Jinwala, Felecia N; Gupta, Mayank

2012-12-01

207

Affect dysregulation in cannabis abusers  

Microsoft Academic Search

Psychiatric comorbidity and impaired emotional functioning have been previously reported in adult substance abusers but have\\u000a been less well documented in adolescents. Thus, we investigated mental health problems and emotion regulation abilities in\\u000a adolescents and young adults with cannabis dependence. Moreover, we explored the relationships between consumption modalities\\u000a and affective style. Therefore, 32 cannabis abusers (CA) and 30 healthy controls

Géraldine Dorard; Sylvie Berthoz; Olivier Phan; Maurice Corcos; Catherine Bungener

2008-01-01

208

Opioid antagonism enhances marijuana's effects in heavy marijuana smokers  

Microsoft Academic Search

Rationale and objective  Studies in laboratory animals strongly suggest reciprocal modulation of the opioidergic and endocannabinoid systems, a relationship\\u000a that has not been demonstrated in humans. This study sought to clarify this interaction by assessing how a range of naltrexone\\u000a doses altered the subjective, cognitive, and cardiovascular effects of marijuana.\\u000a \\u000a \\u000a \\u000a \\u000a Material and methods  Daily marijuana smokers (n?=?29) participated in this within-subject, randomized,

Ziva D. Cooper; Margaret Haney

2010-01-01

209

Acute Marijuana Effects on Human Risk Taking  

Microsoft Academic Search

Previous studies have established a relationship between marijuana use and risky behavior in natural settings. A limited number of laboratory investigations of marijuana effects on human risk taking have been conducted. The present study was designed to examine the acute effects of smoked marijuana on human risk taking, and to identify behavioral mechanisms that may be involved in drug-induced changes

Don R Cherek; Oleg V Tcheremissine; Lori M Lieving; Cythia J Pietras

2005-01-01

210

Marijuana: A Study of State Policies & Penalties.  

ERIC Educational Resources Information Center

This study is a comprehensive analysis of issues concerning marijuana that are of importance to state policy makers. It reviews the medical, legal, and historical dimensions of marijuana use and examines the range of policy approaches toward marijuana possession and use which state officials have considered. Attention is directed to the experience…

Peat, Marwick, Mitchell and Co., Columbia, MD.

211

The Peer Group and Marijuana Use  

Microsoft Academic Search

Based on a survey of 1,704 suburban adolescents and guided by Sutherland's theory of differential association, this paper focuses on the peer group and marijuana use. The peer group is said to be particularly influential in the initial and continued use of marijuana.This paper tests the following two hypotheses as they relate to marijuana use, defined here as a deviant

Nechama Tec

1972-01-01

212

Effects of Marijuana on Fetal Development.  

ERIC Educational Resources Information Center

Presents an historical perspective of the public view of marijuana and examines current empirical research concerning the consequences of marijuana use on the human fetus. Included are 1979 university survey results which explore respondents' knowledge about the effects of marijuana and the relationship this has to the mass media. (Author)

Hoyt, Les Leanne

1981-01-01

213

Marijuana Use Among Miami's Adolescents, 1992  

Microsoft Academic Search

This analysis examines the use of marijuana by 458 adolescents in Dade County, Florida public schools in 1992. Statistically significant factors which tended to increase the probability of marijuana use by adolescents include: the fact that their peers were using marijuana, the fact that they were white, male, and their ready access to the substance. Although not statistically significant, adolescents

Barbara M. Yarnold; Valerie Patterson

1998-01-01

214

Sex, Drugs, and Cognition: Effects of Marijuana  

Microsoft Academic Search

Despite the knowledge that many drugs affect men and women differently, few studies exploring the effects of marijuana use on cognition have included women. Findings from both animal and human studies suggest marijuana may have more marked effects in women. This study examined sex differences in the acute effects of marijuana on cognition in 70 (n = 35 male, 35

Beth M. Anderson; Matthew Rizzo; Robert I. Block; Godfrey D. Pearlson; Daniel S. OLeary

2010-01-01

215

Marijuana: Facts Parents Need To Know.  

ERIC Educational Resources Information Center

Marijuana is the illegal drug most often used in the United States. In the early 1990s marijuana use doubled among 8th graders and significantly increased among 10th and 12th graders. Accompanying this pattern of use is a significant erosion in antidrug perceptions and knowledge among young people. While marijuana use among high school seniors…

National Inst. on Drug Abuse (DHHS), Rockville, MD. Div. of Research.

216

Oilseed crop: Camelina sativa  

Microsoft Academic Search

False flax and gold of pleasure are the popular names for Camelina sativa (L.) Crantz. Seeds and capsules of Camelina sativa ssp. C. linicola (Schimp. and Spenn.), have been found in archaeological excavations from the Bronze Age in Scandinavia and Western Europe. C. sativa was grown as an agricultural crop in European countries and Russia before the Second World War

Josef Zubr

1997-01-01

217

Cannabis-induced Koro in Americans  

Microsoft Academic Search

Aims. Koro, an acute panic reaction related to the perception of penile retraction, was once considered limited to specié c cultures. The disorder has appeared as part of a panic response to cannabis, but only in citizens of India. This study looked for cannabis-induced Koro in Americans. Design. Given the relative rarity of cannabis-induced Koro, this work focused on individual

Mitchell Earleywine

2001-01-01

218

On the pharmaceuticalization of marijuana  

Microsoft Academic Search

Given the very limited toxicity of marijuana and the growing appreciation of its therapeutic value, it will undoubtedly find increasing application as a medicine in the coming years. But there is uncertainty about the forms in which it will be made available. Governments are hesitant to approve it because of concern about its use for nonmedical purposes and the difficulties

Lester Grinspoon

2001-01-01

219

Behavioral Aspects of Marijuana Use.  

ERIC Educational Resources Information Center

This paper examines the behavioral aspects of marijuana use. The focus of the study was to investigate the attitudes and practices toward drugs by users and non-users and the relationship of these attitudes and practices to selected psychosocial factors. A survey instrument in the form of an anonymous questionnaire was developed and administered…

Paulson, Patricia

220

Marijuana: Use Among Young Males and Health Outcomes  

Microsoft Academic Search

Marijuana is the most commonly used illicit drug by adolescents and young adults, with more males than females reporting marijuana use. The adolescent and young adult years represent a critical period for interventions to prevent marijuana use and abuse. This article reviews relevant literature, including trends in young males’ marijuana use and health effects of marijuana use. By most measures,

Melissa Pujazon-Zazik; M. Jane Park

2009-01-01

221

Jason B. West,1 Ph.D.; Janet M. Hurley,1  

E-print Network

outdoor growth. KEYWORDS: forensic science, stable isotope ratio, drug intelligence, Cannabis sativa Marijuana (Cannabis sativa L.) is the most widely used illicit drug in the United States (1­4) and is associated with a range of public health concerns (e.g., 5, 6­12). In spite of this, there remains

Ehleringer, Jim

222

Cannabis psychosis and paranoid schizophrenia.  

PubMed

The initial clinical symptoms of 25 consecutive cases of cannabis psychosis of the paranoid type and 25 consecutive cases of paranoid schizophrenia were studied and compared, in order to delineate features that would enable a differentiation of the two conditions. It was observed that the patients with cannabis psychosis substantially differed in terms of behavioral manifestations. Most of these patients were violent and panicky and demonstrated bizzare behavior, but they possessed some insight into the nature of their illness. Schizophrenic patients manifested these disturbances and characteristics less frequently. Subjects with cannabis psychosis showed rapid ideation and flight of ideas, whereas the characteristic schizophrenic thought-disorder was found mostly in schizophrenic patients. PMID:1259526

Thacore, V R; Shukla, S R

1976-03-01

223

[Cannabis and the lung - chill or kill?].  

PubMed

Cannabis is the most widely consumed illicit drug in the western world. Cannabis and tobacco smoke contain a similar mix of irritant and toxic chemicals. Therefore, there are reasons to suspect, that cannabis and tobacco have similar side effects. However, the pulmonary effects of smoking cannabis have not been extensively researched and the few findings are contradictory. Among the reasons for this uncertainty are its illegal status and the common practice of combining cannabis with tobacco. Separating the effects of the two substances is therefore difficult. PMID:20687046

Grendelmeier, Peter

2010-08-01

224

The Interface: Marijuana and Body Weight  

PubMed Central

Acute marijuana use is classically associated with snacking behavior (colloquially referred to as “the munchies”). In support of these acute appetite-enhancing effects, several authorities report that marijuana may increase body mass index in patients suffering from human immunodeficiency virus and cancer. However, for these medical conditions, while appetite may be stimulated, some studies indicate that weight gain is not always clinically meaningful. In addition, in a study of cancer patients in which weight gain did occur, it was less than the comparator drug (megestrol). However, data generally suggest that acute marijuana use stimulates appetite, and that marijuana use may stimulate appetite in low-weight individuals. As for large epidemiological studies in the general population, findings consistently indicate that users of marijuana tend to have lower body mass indices than nonusers. While paradoxical and somewhat perplexing, these findings may be explained by various study confounds, such as potential differences between acute versus chronic marijuana use; the tendency for marijuana use to be associated with other types of drug use; and/or the possible competition between food and drugs for the same reward sites in the brain. Likewise, perhaps the effects of marijuana are a function of initial weight status—i.e., maybe marijuana is a metabolic regulatory substance that increases body weight in low-weight individuals but not in normal-weight or overweight individuals. Only further research will clarify the complex relationships between marijuana and body weight. PMID:25337447

Sansone, Lori A.

2014-01-01

225

The interface: marijuana and body weight.  

PubMed

Acute marijuana use is classically associated with snacking behavior (colloquially referred to as "the munchies"). In support of these acute appetite-enhancing effects, several authorities report that marijuana may increase body mass index in patients suffering from human immunodeficiency virus and cancer. However, for these medical conditions, while appetite may be stimulated, some studies indicate that weight gain is not always clinically meaningful. In addition, in a study of cancer patients in which weight gain did occur, it was less than the comparator drug (megestrol). However, data generally suggest that acute marijuana use stimulates appetite, and that marijuana use may stimulate appetite in low-weight individuals. As for large epidemiological studies in the general population, findings consistently indicate that users of marijuana tend to have lower body mass indices than nonusers. While paradoxical and somewhat perplexing, these findings may be explained by various study confounds, such as potential differences between acute versus chronic marijuana use; the tendency for marijuana use to be associated with other types of drug use; and/or the possible competition between food and drugs for the same reward sites in the brain. Likewise, perhaps the effects of marijuana are a function of initial weight status-i.e., maybe marijuana is a metabolic regulatory substance that increases body weight in low-weight individuals but not in normal-weight or overweight individuals. Only further research will clarify the complex relationships between marijuana and body weight. PMID:25337447

Sansone, Randy A; Sansone, Lori A

2014-07-01

226

Exposure to Cannabis in Popular Music and Cannabis Use among Adolescents  

PubMed Central

Background Cannabis use is frequently referenced in American popular music, yet it remains uncertain whether exposure to these references is associated with actual cannabis use. We aimed to determine if exposure to cannabis in popular music is independently associated with current cannabis use in a cohort of urban adolescents. Methods We surveyed all 9th grade students at three large U.S. urban high schools. We estimated participants’ exposure to lyrics referent to cannabis with overall music exposure and content analyses of their favorite artists’ songs. Outcomes included current (past 30 day) and ever use of cannabis. We used multivariable regression to assess independent associations between exposures and outcomes while controlling for important covariates. Results Each of the 959 participants was exposed to an estimated 40 cannabis references per day (standard deviation = 104). Twelve percent (N = 108) were current cannabis users and 32% (N=286) had ever used cannabis. Compared with those in the lowest tertile of total cannabis exposure in music, those in the highest tertile of exposure were almost twice as likely to have used cannabis in the past 30 days (odds ratio = 1.83; 95% confidence interval = 1.04, 3.22), even after adjusting for sociodemographic variables, personality characteristics, and parenting style. As expected, however, there was no significant relationship between our cannabis exposure variable and a sham outcome variable of alcohol use. Conclusions This study supports an independent association between exposure to cannabis in popular music and early cannabis use among urban American adolescents. PMID:20039860

Primack, Brian A.; Douglas, Erika L.; Kraemer, Kevin L.

2009-01-01

227

A Randomized Double-blind, Placebo Controlled Trial of Venlafaxine-Extended Release for Co-occurring Cannabis Dependence and Depressive Disorders  

PubMed Central

Aim To evaluate whether venlafaxine-extended release (VEN-XR) is an effective treatment for cannabis dependence with concurrent depressive disorders. Design This was a randomized, 12 week, double-blind, placebo-controlled trial of outpatients (n = 103) with DSM-IV cannabis dependence and major depressive disorder or dysthymia. Participants received up to 375 mg VEN-XR on a fixed-flexible schedule or placebo. All patients received weekly individual cognitive-behavioral psychotherapy that primarily targeted marijuana use. Settings The trial was conducted at two university research centers in the United States. Participants One hundred and three cannabis dependent adults participated in the trial. Measurements The primary outcome measures were 1) abstinence from marijuana defined as at least two consecutive urine-confirmed abstinent weeks and 2) improvement in depressive symptoms based on the Hamilton Depression Rating Scale. Findings The proportion of patients achieving a clinically significant mood improvement [50% decrease in Hamilton Depression score from baseline] was high and did not differ between groups receiving VEN-XR (63%) and placebo (69%) (X12=0.48, p-value= 0.49). The proportion of patients achieving abstinence was low overall, but was significantly worse on VEN-XR (11.8%) compared to placebo (36.5%) (X12=7.46, p-value<0.01; OR = 4.51, 95% CI: 1.53, 13.3). Mood improvement was associated with reduction in marijuana use in the placebo group (F1,179=30.49, p-value<0.01), but not the VEN-XR group (F1,186=0.02, p-value=0.89). Conclusions For depressed, cannabis-dependent patients, venlafaxine-extended release does not appear to be effective at reducing depression and may lead to an increase in cannabis use. PMID:23297841

Levin, Frances R.; Mariani, John; Brooks, Daniel J.; Pavlicova, Martina; Nunes, Edward V.; Agosti, Vito; Bisaga, Adam; Sullivan, Maria A.; Carpenter, Kenneth M.

2013-01-01

228

Medical marijuana diversion and associated problems in adolescent substance treatment  

Microsoft Academic Search

BackgroundThe prevalence of medical marijuana diversion among adolescents in substance treatment and the relationship between medical marijuana diversion and marijuana attitudes, availability, peer disapproval, frequency of use and substance-related problems are not known.

Christian Thurstone; Shane A. Lieberman; Sarah J. Schmiege

2011-01-01

229

Medical marijuana--is it safe?  

PubMed

Many people have used medical marijuana to manage symptoms of HIV infection and side effects of therapies. Medical marijuana users assert that the drug is useful in treating nausea, increasing appetite or as a mild analgesic (to help with headaches or mild pain). However, people living with HIV have been left with unclear information as to the risks and benefits of medical marijuana use. PMID:12171024

2000-10-01

230

7 CFR 400.677 - Definitions.  

...substance. Any prohibited drug-producing plants including, but not limited to, cacti of the genus (lophophora), coca bushes (erythroxylum coca), marijuana (cannabis sativa), opium poppies (papaver somniferum), and other drug-producing...

2014-01-01

231

7 CFR 400.677 - Definitions.  

Code of Federal Regulations, 2013 CFR

...substance. Any prohibited drug-producing plants including, but not limited to, cacti of the genus (lophophora), coca bushes (erythroxylum coca), marijuana (cannabis sativa), opium poppies (papaver somniferum), and other drug-producing...

2013-01-01

232

7 CFR 400.677 - Definitions.  

Code of Federal Regulations, 2011 CFR

...substance. Any prohibited drug-producing plants including, but not limited to, cacti of the genus (lophophora), coca bushes (erythroxylum coca), marijuana (cannabis sativa), opium poppies (papaver somniferum), and other drug-producing...

2011-01-01

233

7 CFR 400.677 - Definitions.  

Code of Federal Regulations, 2012 CFR

...substance. Any prohibited drug-producing plants including, but not limited to, cacti of the genus (lophophora), coca bushes (erythroxylum coca), marijuana (cannabis sativa), opium poppies (papaver somniferum), and other drug-producing...

2012-01-01

234

7 CFR 400.677 - Definitions.  

Code of Federal Regulations, 2010 CFR

...substance. Any prohibited drug-producing plants including, but not limited to, cacti of the genus (lophophora), coca bushes (erythroxylum coca), marijuana (cannabis sativa), opium poppies (papaver somniferum), and other drug-producing...

2010-01-01

235

Industrial Hemp in the United States: Status and Market Potential.  

National Technical Information Service (NTIS)

Industrial hemp has been the focus of official interest in several States. However, hemp and marijuana are different varieties of Cannabis sativa, which is classified as a controlled substance in the United States. With Canada now allowing hemp production...

2000-01-01

236

Medical Marijuana: Tribulations and Trials  

Microsoft Academic Search

Widespread use of smoked marijuana in the San Francisco Bay Area as a treatment for HIV-related anorexia and weight loss, as well as nausea related to prescribed therapy, prompted the design of a clinical trial to evaluate the safety and effectiveness of this controlled substance. The Community Consortium—the Bay Area's community-based HIV clinical trials organization—designed a first pilot evaluation of

Donald I. Abrams

1998-01-01

237

Anticoagulant effects of a Cannabis extract in an obese rat model.  

PubMed

Blood coagulation studies were conducted to determine the possible anti-/prothrombotic effect of an organic cannabis extract and the three major cannabinoids, THC, CBD and CBN. The in vitro effect of the cannabis extract on thrombin activity produced an IC50 value of 9.89 mg/ml, compared to THC at 1.79 mg/ml. It was also found that the extract, THC and CBN showed considerable inhibition of thrombin-induced clot formation in vitro with IC50 values of 600, 87 and 83 microg/ml for the extract, THC and CBN respectively. In an in vivo model used to determine clotting times of lean and obese rats treated with a cannabis extract, 50% clotting times were found to be 1.5 and 2 fold greater than their respective control groups, supporting the results obtained in the in vitro model. The study thus shows that Cannabis sativa and the cannabinoids, THC and CBN, display anticoagulant activity and may be useful in the treatment of diseases such as type 2 diabetes in which a hypercoagulable state exists. PMID:16644197

Coetzee, C; Levendal, R-A; van de Venter, M; Frost, C L

2007-05-01

238

Cannabis use among youth in the Netherlands.  

PubMed

A nation-wide survey of cannabis use, based on a representative sample of 1,306 young people in the 15-to-24 age group, carried out in the Netherlands in 1983, showed that cannabis had been used or tried by 12.2 per cent of the respondents (13 per cent males and 11 per cent females). These results, compared with the results of a study carried out by the Central Bureau of Statistics in 1979 and 1980, showed an increase in cannabis use. In the three largest cities, the percentage of cannabis users (25 per cent) was double that of the country as a whole. The percentage of cannabis use was higher among the older age groups of respondents; the study also showed that the lower the age at first cannabis use the higher the risk of continuing and becoming involved with more dangerous drugs such as cocaine, heroin and amphetamines. The rates of alcohol drinking, tobacco smoking and the use of heroin, amphetamines, cocaine, sleeping pills and tranquillizers were significantly higher among cannabis users than among respondents who were not using cannabis. The rate of cannabis use was significantly higher among the unemployed respondents than among those who had a job. The authors suggest that these findings should be taken into account in designing preventive measures and other forms of intervention programmes to deal with cannabis-related problems among young people. PMID:3879668

Sylbing, G; Persoon, J M

1985-01-01

239

Medical marijuana laws in 50 states: Investigating the relationship between state legalization of medical marijuana and marijuana use, abuse and dependence  

Microsoft Academic Search

BackgroundMarijuana is the most frequently used illicit substance in the United States. Little is known of the role that macro-level factors, including community norms and laws related to substance use, play in determining marijuana use, abuse and dependence. We tested the relationship between state-level legalization of medical marijuana and marijuana use, abuse, and dependence.

Magdalena Cerdá; Melanie Wall; Katherine M. Keyes; Sandro Galea; Deborah Hasin

240

Quantifying the Clinical Significance of Cannabis Withdrawal  

PubMed Central

Background and Aims Questions over the clinical significance of cannabis withdrawal have hindered its inclusion as a discrete cannabis induced psychiatric condition in the Diagnostic and Statistical Manual of Mental Disorders (DSM IV). This study aims to quantify functional impairment to normal daily activities from cannabis withdrawal, and looks at the factors predicting functional impairment. In addition the study tests the influence of functional impairment from cannabis withdrawal on cannabis use during and after an abstinence attempt. Methods and Results A volunteer sample of 49 non-treatment seeking cannabis users who met DSM-IV criteria for dependence provided daily withdrawal-related functional impairment scores during a one-week baseline phase and two weeks of monitored abstinence from cannabis with a one month follow up. Functional impairment from withdrawal symptoms was strongly associated with symptom severity (p?=?0.0001). Participants with more severe cannabis dependence before the abstinence attempt reported greater functional impairment from cannabis withdrawal (p?=?0.03). Relapse to cannabis use during the abstinence period was associated with greater functional impairment from a subset of withdrawal symptoms in high dependence users. Higher levels of functional impairment during the abstinence attempt predicted higher levels of cannabis use at one month follow up (p?=?0.001). Conclusions Cannabis withdrawal is clinically significant because it is associated with functional impairment to normal daily activities, as well as relapse to cannabis use. Sample size in the relapse group was small and the use of a non-treatment seeking population requires findings to be replicated in clinical samples. Tailoring treatments to target withdrawal symptoms contributing to functional impairment during a quit attempt may improve treatment outcomes. PMID:23049760

Allsop, David J.; Copeland, Jan; Norberg, Melissa M.; Fu, Shanlin; Molnar, Anna; Lewis, John; Budney, Alan J.

2012-01-01

241

Prospective Assessment of Cannabis Withdrawal in Adolescents with Cannabis Dependence: A Pilot Study  

ERIC Educational Resources Information Center

A study to identify and assess the withdrawal symptoms in adolescents afflicted with cannabis dependence is conducted. Results conclude that withdrawal symptoms of cannabis were present in adolescents seeking treatment for this substance abuse.

Milin, Robert; Manion, Ian; Dare, Glenda; Walker, Selena

2008-01-01

242

Validation of the Cannabis Expectancy Questionnaire (CEQ) in adult cannabis users in treatment  

Microsoft Academic Search

BackgroundOutcome expectancies are a key cognitive construct in the etiology, assessment and treatment of Substance Use Disorders. There is a research and clinical need for a cannabis expectancy measure validated in a clinical sample of cannabis users.

Jason P. Connor; Matthew J. Gullo; Gerald F. X. Feeney; Ross Mc D. Young

2011-01-01

243

Pathways to Psychosis in Cannabis Abuse.  

PubMed

Cannabis has been implicated as a risk factor for the development of schizophrenia, but the exact biological mechanisms remain unclear. In this review, we attempt to understand the neurobiological pathways that link cannabis use to schizophrenia. This has been an area of great debate; despite similarities between cannabis users and schizophrenia patients, the evidence is not sufficient to establish cause-and-effect. There have been advances in the understanding of the mechanisms of cannabis dependence as well as the role of the cannabinoid system in the development of psychosis and schizophrenia. The neurobiological mechanisms associated with the development of psychosis and effects from cannabis use may be similar but remains elusive.. In order to better understand these associations, this paper will show common neurobiological and neuroanatomical changes as well as common cognitive dysfunction in cannabis users and patients of schizophrenia.. We conclude that epidemiologic evidence highlights potential causal links; however neurobiological evidence for causality remains weak. PMID:23491968

Shrivastava, Amresh; Johnston, Megan; Terpstra, Kristen; Bureau, Yves

2013-03-14

244

The Cannabis Use Problems Identification Test (CUPIT) : development and psychometrics.  

E-print Network

??Lack of a brief empirically-verified screener for problematic and potentially problematic cannabis use has hampered implementation of a proactive opportunistic cannabis screening and early intervention… (more)

Bashford, Janet Lorraine

2007-01-01

245

Marijuana and the Use of Other Drugs  

Microsoft Academic Search

IT is well established that the use of marijuana by young people is positively correlated with at least the experimental use of other drugs1. The probability that an individual uses the strong hallucinogens such as LSD and other drugs rises sharply with increasing frequency of marijuana use2. Such associations are not, of course, sufficient to establish causal relationships between the

William McGlothlin; Kay Jamison; Steven Rosenblatt

1970-01-01

246

Marijuana: Implications of Use by Young People.  

ERIC Educational Resources Information Center

Uses survey and interview data and recent findings to consider the marijuana problem in the following areas: marijuana use at an early age and for negative reasons; drug effects leading to learning impairment and school behavior problems; young people lacking accurate information; and usage leading to other drug use. (Author/RC)

Lamanna, Michael

1981-01-01

247

Medical marijuana: medical necessity versus political agenda.  

PubMed

Marijuana is classified by the Drug Enforcement Agency (DEA) as an illegal Schedule I drug which has no accepted medical use. However, recent studies have shown that medical marijuana is effective in controlling chronic non-cancer pain, alleviating nausea and vomiting associated with chemotherapy, treating wasting syndrome associated with AIDS, and controlling muscle spasms due to multiple sclerosis. These studies state that the alleviating benefits of marijuana outweigh the negative effects of the drug, and recommend that marijuana be administered to patients who have failed to respond to other therapies. Despite supporting evidence, the DEA refuses to reclassify marijuana as a Schedule II drug, which would allow physicians to prescribe marijuana to suffering patients. The use of medical marijuana has continued to gain support among states, and is currently legal in 16 states and the District of Columbia. This is in stark contrast to the federal government's stance of zero-tolerance, which has led to a heated legal debate in the United States. After reviewing relevant scientific data and grounding the issue in ethical principles like beneficence and nonmaleficence, there is a strong argument for allowing physicians to prescribe marijuana. Patients have a right to all beneficial treatments and to deny them this right violates their basic human rights. PMID:22129912

Clark, Peter A; Capuzzi, Kevin; Fick, Cameron

2011-12-01

248

Marijuana: The Real Story. It's Your Choice!  

ERIC Educational Resources Information Center

This informational book on marijuana is part of a series of three interactive books on tobacco, alcohol, and marijuana; three informational books containing parallel content; and three teacher guides designed to give students in grades five through eight practice in using the information and skills presented in the books. The goal of this book and…

Stronck, David R.

249

A Synthesis of Current Research On Marijuana  

ERIC Educational Resources Information Center

Since the isolation of the active component of marijuana (THC), studies have revealed various effects to the memory, specific physiological effects, and definite visual effects to individuals while under the influence of marijuana. The sociological aspects of the drug may stimulate an individual into the use of this drug. (Author)

Brubaker, Timothy H.

1973-01-01

250

The Effects of Marijuana on Human Cognition.  

ERIC Educational Resources Information Center

Investigating the effects of marijuana on human psychological functioning, this study differs from previous research in two ways: 1) it is concerned with relatively complex cognitive processes; 2) it has a theoretical rationale. The general hypothesis of the study states that marijuana will impair its user's ability to form and use abstract…

Pearl, Joseph H.

251

Robin Room and cannabis policy: Dangerous comparisons.  

PubMed

This paper describes Robin Room's contribution to cannabis policy debates over the period 1993-2010. It focuses on a controversy that erupted over a review that Room and the author undertook for the World Health Organization in the mid-1990s on the comparative harms of cannabis, alcohol, opiates and tobacco. It also briefly describes Room's recent work on global cannabis policy and ends with a brief appreciation of the character of his scholarly contributions to this field. [Hall W. Robin Room and cannabis policy: Dangerous comparisons. Drug Alcohol Rev 2014]. PMID:25395172

Hall, Wayne

2014-11-01

252

Functional Consequences of Marijuana Use in Adolescents  

PubMed Central

Nearly half of 12th graders have tried marijuana, and 6% use daily. This paper reviews studies on neuropsychological functioning, brain structure, brain function, and subjective and objective measures of sleep in relation to adolescent marijuana use. Adolescents who use marijuana heavily tend to show disadvantaged attention, learning, and processing speed; subtle abnormalities in brain structure; increased activation during cognitive tasks despite intact performance; and compromised objective indicators of sleep quality. Some abnormalities appear to persist beyond a month of abstinence, but may resolve within three months if cessation is maintained. Recommendations for future studies include characterizing these indices in youth prior to the onset of marijuana use then examining change after chronic use has started, and using large samples of youth with varying degrees of involvement with marijuana as well as alcohol, nicotine, and other drugs to characterize the interactive influences on neurocognition and neural health. PMID:19348837

Jacobus, J.; Bava, S.; Cohen-Zion, M.; Mahmood, O.; Tapert, S. F.

2009-01-01

253

Medical marijuana: more questions than answers.  

PubMed

With 23 states and the District of Columbia having enacted medical marijuana laws as of August 2014, it is important that psychiatrists be able to address questions about medical marijuana from patients, families, and other health care professionals. The author discusses the medical literature on synthetic cannabinoids and medical marijuana. The synthetic cannabinoids dronabinol and nabilone are approved by the United States Food and Drug Administration for nausea and vomiting associated with cancer chemotherapy and appetite stimulation in patients with wasting diseases such as acquired immunodeficiency syndrome (AIDS). Results of clinical trials of these agents for other conditions have varied widely thus far. In addition, few data are available on the use of the marijuana plant as a medical treatment. The author concludes that there is a clear need for additional research on possible medical uses of cannabinoids. He notes that discussions with prospective medical marijuana patients should emphasize the importance of communication among all parties due to the possible side effects of treatment with marijuana and its potential to interact with other medications the patient may be taking. Facilitating a thorough substance abuse consultation is one of most positive ways that psychiatrists, especially addiction psychiatrists, can make an impact as medical marijuana becomes increasingly common. A careful review of the prospective medical marijuana user's substance use history, co-occurring medical and psychiatric conditions, family history, and psychosocial stressors is essential in evaluating the potential risks of medical marijuana for these patients. The author concludes that psychiatrists can have a significant impact by increasing the likelihood that medical marijuana will be used in a safe and responsible way. PMID:25226202

Hill, Kevin P

2014-09-01

254

Cannabis use and oral diseases  

Microsoft Academic Search

Data sourcesMedline and the Cochrane Central register of controlled trails (CENTRAL).Study selectionRandomised Controlled Trials, Controlled Clinical Trials and Cohort Studies conducted on humans investigating cannabis usage were included. Screening was performed independently by two reviewers. Only English language studies were included. Case reports, letters and historical reviews were excluded.Data extraction and synthesisA narrative synthesis was conducted.ResultsSeven studies were included and

Analia Veitz-Keenan; Silvia Spivakovsky

2011-01-01

255

Laboratory detection of marijuana use. Experience with a photometric immunoassay to measure urinary cannabinoids.  

PubMed

The urinary excretion of cannabinoids was determined using a photometric immunoassay technique among adolescents and young adults who had an abrupt and closely supervised cessation of drug use on entering a strict rehabilitation program. No falsely positive urine test results were encountered among 70 persons admitted consecutively to the program. Among five subjects with a history of chronic, heavy marijuana use (approximately 56 g/mo [approximately 2 oz/mo]), urinary cannabinoids were detected for an average of 13 days (range, nine to 25 days), following cessation of use. Among four subjects with a history of moderate marijuana use (approximately 28 g/mo [approximately 1 oz/mo]), test results remained positive for an average of 4.7 days (range, two to eight days). Test results were negative 48 hours after cessation in two subjects with a history of infrequent use (less than 7 g/mo [0.25 oz/mo]), who had smoked marijuana within the preceding two days. The specificity of the method for detecting recent marijuana use appears excellent; the sensitivity depends on the potency of the cannabis preparation, the time of last use, the frequency of previous use, and the specific gravity of the urine specimen. On the basis of this preliminary experience, positive test results for more than eight consecutive days suggest either surreptitious continued use or previous chronic, heavy use in a newly abstinent person. Purposeful adulteration of known-positive urine specimens with bleach, blood, vinegar, salt, and liquid soap produced falsely negative results. Unless samples are collected under direct observation, urine color, temperature, specific gravity, and dipstick tests for blood and pH should be recorded. PMID:3904404

Schwartz, R H; Hayden, G F; Riddile, M

1985-11-01

256

Marijuana's Effects on Human Cognitive Functions, Psychomotor Functions, and Personality  

Microsoft Academic Search

Marijuana is complex chemically and not yet fully understood, but it is not a narcotic. Like alcohol, marijuana acts as both stimulant and depressant, but it lingers in body organs longer than alcohol. Smoking marijuana can injure mucosal tissue and may have more carcinogenic potential than tobacco. Research has indicated that marijuana intoxication definitely hinders attention, long-term memory storage, and

John B. Murray

1986-01-01

257

The Influence of Marijuana Use on Neurocognitive Functioning in Adolescents  

Microsoft Academic Search

Marijuana use is common in adolescence, yet neural consequences have not been well delineated. This review seeks to ascertain whether heavy marijuana use in adolescence is associated with persistent neurocognitive abnormalities, and whether adolescents are more vulnerable to the impact of chronic marijuana use than adults. Among heavy marijuana using adults, neurocognitive deficits are apparent for several days following use,

Alecia D. Schweinsburg; Sandra A. Brown; Susan F. Tapert

2008-01-01

258

Medical marijuana and driving: a review.  

PubMed

Medical marijuana remains a highly debated treatment regimen despite removal of state penalties against care providers prescribing the drug and patients treated with the drug in many areas of the USA. The utility of marijuana in specific medical conditions has been studied at length, but its effects on driving performance and risk of motor vehicle collision remain unclear. As with other medications that affect psychomotor function, the healthcare provider should be informed of the potential risks of driver safety prior to prescribing this psychotropic drug to give appropriate anticipatory guidance for appropriate use. The goal of this narrative review is to assess the current literature regarding marijuana as it relates to driving performance and traffic safety. With a foundation in the pharmacology of cannabinoids, we consider the limitations of testing cannabinoid and metabolite concentration. In addition, we will review studies on driving performance and epidemiological studies implicating marijuana in motor vehicle collisions. The increasing prevalence of medical marijuana laws in the USA suggests that clinicians should be aware of marijuana's influence on public safety. Patients should abstain from driving for 8 h if they achieve a subjective "high" from self-treatment with smoked marijuana and should be aware of the cumulative effects of alcohol and other psychoactive xenobiotics. PMID:24648180

Neavyn, Mark J; Blohm, Eike; Babu, Kavita M; Bird, Steven B

2014-09-01

259

Cannabis Use and Mental Health Problems  

Microsoft Academic Search

Cannabis is the most widely used illicit drug. Over the last thirty years, the age at which it is first used has fallen and lifetime prevalence has risen in most developed countries. Cannabis' popularity is derived from the mild euphoria associated with its consumption and from the generally held belief that its health consequences are rather benign. However, there is

Jenny Williams; Jan van Ours

2010-01-01

260

Cannabis and Psychosis Put in Perspective  

Microsoft Academic Search

n this issue, Louisa Degenhardt and Wayne Hall provide an insightful and accessible overview of the literature on the relation between cannabis use and psychosis. They also present some of the policy implications of this relation. The first paper reviews the evidence for a causal relation between cannabis use during adolescence and early adulthood and subsequent diagnosis of a psychotic

Richard P Mattick; Jennifer McLaren

261

Medical Cannabis Patients: Patient Profiles and Health Care Utilization Patterns  

Microsoft Academic Search

The possible medicinal uses of cannabis are growing, yet research on how patients use medical cannabis facility services remains scarce. This article reports on the Cannabis Care Study, in which 130 medical cannabis patients at seven facilities in the San Francisco Bay Area were surveyed to gather information about demographics, personal health practices, health outcomes, service use, and satisfaction with

Amanda Reiman

2007-01-01

262

Quality of Web-Based Information on Cannabis Addiction  

ERIC Educational Resources Information Center

This study evaluated the quality of Web-based information on cannabis use and addiction and investigated particular content quality indicators. Three keywords ("cannabis addiction," "cannabis dependence," and "cannabis abuse") were entered into two popular World Wide Web search engines. Websites were assessed with a standardized proforma designed…

Khazaal, Yasser; Chatton, Anne; Cochand, Sophie; Zullino, Daniele

2008-01-01

263

Marijuana-Related Problems and Social Anxiety: The Role of Marijuana Behaviors in Social Situations  

Microsoft Academic Search

Individuals with elevated social anxiety appear particularly vulnerable to marijuana-related problems. In fact, individuals with social anxiety may be more likely to experience marijuana-related impairment than individuals with other types of anxiety. It is therefore important to determine whether constructs particularly relevant to socially anxious individuals play a role in the expression of marijuana-related problems in this vulnerable population. Given

Julia D. Buckner; Richard G. Heimberg; Russell A. Matthews; Jose Silgado

2012-01-01

264

Baclofen in the management of cannabis dependence syndrome  

PubMed Central

Cannabis is the most commonly used illicit drug in the world. However, only few studies have shown the efficacy of pharmacologic agents in targeting cannabis withdrawal symptoms or reducing the reinforcing effects of cannabis. Baclofen has been shown to reduce cannabis withdrawal symptoms and the subjective effects of cannabis. We think that the clinical utility of baclofen for cannabis dependence is a reasonable approach. A case report using baclofen is presented and provides preliminary support for the use of baclofen in the management of cannabis dependence. PMID:24490032

Labrune, Nathalie; Lancon, Christophe; Simon, Nicolas

2014-01-01

265

The context of desire to use marijuana: momentary assessment of young people who frequently use marijuana.  

PubMed

Drawing on factors identified in the literature, this study explored in-the-moment associations of social, emotional, and temporal contexts and perceived marijuana availability with desire to use the drug, using momentary sampling methodology with young people who frequently use marijuana. Forty-one adolescent/young adult medical outpatients aged 15 to 24 years who reported using marijuana at least twice a week completed 2,912 brief questionnaires on a handheld computer in response to signals emitted at random four to six times a day for 2 weeks. The questionnaires assessed, for the moment when signaled, desire to use marijuana, location, companionship, perceived ease of getting marijuana (availability), positive affect, and negative affect. Participants reported any desire to use marijuana on 1,528 reports (55%). Companionship, perceived availability, and positive affect were independently associated with having any desire to use marijuana. Once desire to use marijuana was present, time of day, positive affect, and negative affect were independently associated with strength of desire. By collecting data in real time, in real life, this study highlights the importance of examining and intervening on emotional, environmental, and temporal contexts for youth who frequently use marijuana in order to reduce their desire to use the drug. PMID:22823544

Shrier, Lydia A; Walls, Courtney E; Kendall, Ashley D; Blood, Emily A

2012-12-01

266

Cannabis cue reactivity and craving among never, infrequent and heavy cannabis users.  

PubMed

Substance cue reactivity is theorized as having a significant role in addiction processes, promoting compulsive patterns of drug-seeking and drug-taking behavior. However, research extending this phenomenon to cannabis has been limited. To that end, the goal of the current work was to examine the relationship between cannabis cue reactivity and craving in a sample of 353 participants varying in self-reported cannabis use. Participants completed a visual oddball task whereby neutral, exercise, and cannabis cue images were presented, and a neutral auditory oddball task while event-related brain potentials (ERPs) were recorded. Consistent with past research, greater cannabis use was associated with greater reactivity to cannabis images, as reflected in the P300 component of the ERP, but not to neutral auditory oddball cues. The latter indicates the specificity of cue reactivity differences as a function of substance-related cues and not generalized cue reactivity. Additionally, cannabis cue reactivity was significantly related to self-reported cannabis craving as well as problems associated with cannabis use. Implications for cannabis use and addiction more generally are discussed. PMID:24264815

Henry, Erika A; Kaye, Jesse T; Bryan, Angela D; Hutchison, Kent E; Ito, Tiffany A

2014-04-01

267

[Results of a standardized survey on the medical use of cannabis products in the German-speaking area].  

PubMed

The plant Cannabis sativa has a long history of medical use in the treatment of pain and spasms, the promotion of sleep, and the suppression of nausea and vomiting. However, in the early 70s cannabis was classified in the Narcotic Acts in countries all over the world as having no therapeutic benefit; therefore, it cannot be prescribed by physicians or dispensed by pharmacists. In the light of this contradictory situation an increasing number of patients practices a self-prescription with cannabis products for relieving a variety of symptoms. An anonymous standardized survey of the medical use of cannabis and cannabis products of patients in Germany, Austria and Switzerland was conducted by the Association for Cannabis as Medicine (Cologne, Germany). During about one year 170 subjects participated in this survey; questionnaires of 128 patients could be included into the evaluation. 68% of these participants were males, 32% females, with a total mean age of 37.5 (+/- 9.6) years. The most frequently mentioned indications for medicinal cannabis use were depression (12.0%), multiple sclerosis (10.8%), HIV-infection (9.0%), migraine (6.6%), asthma (6.0%), back pain (5.4%), hepatitis C (4. 8%), sleeping disorders (4.8%), epilepsy (3.6%), spasticity (3.6%), headache (3.6%), alcoholism (3.0%), glaucoma (3.0%), nausea (3.0%), disk prolapse (2.4%), and spinal cord injury (2.4%). The majority of patients used natural cannabis products such as marihuana, hashish and an alcoholic tincture; in just 5 cases dronabinol (Marinol) was taken by prescription. About half of the 128 participants of the survey (52.4%) had used cannabis as a recreational drug before the onset of their illness. To date 14.3% took cannabis orally, 49.2% by inhalation and in 36.5% of cases both application modes were used. 72.2% of the patients stated the symptoms of their illness to have 'much improved' after cannabis ingestion, 23.4% stated to have 'slightly improved', 4.8% experienced 'no change' and 1.6% described that their symptoms got 'worse'. Being asked for the satisfaction with their therapeutic use of cannabis 60.8% stated to be 'very satisfied', 24.0% 'satisfied', 11.2% 'partly satisfied' and 4.0% were 'not satisfied'. 70.8% experienced no side effects, 26.4% described 'moderate' and 3.3% 'strong' side effects. 84.1% of patients have not felt any need for dose escalation during the last 3 months, 11.0% had to increase their cannabis dose 'moderately' and 4.8% 'strongly' in order to maintain the therapeutic effects. Thus, this survey demonstrates a successful use of cannabis products for the treatment of a multitude of various illnesses and symptoms. This use was usually accompanied only by slight and in general acceptable side effects. Because the patient group responding to this survey is presumably highly selected, no conclusions can be drawn about the quantity of wanted and unwanted effects of the medicinal use of the hemp plant for particular indications. PMID:10575286

Schnelle, M; Grotenhermen, F; Reif, M; Gorter, R W

1999-10-01

268

Paternal determinants of female adolescent's marijuana use  

Microsoft Academic Search

The purpose of this study was to examine the interrelationship of sets of paternal personality attributes, paternal–daughter relationship variables, and adolescent personality factors with adolescent daughters' use of marijuana. This was a follow-up of a previous study examining father–son factors related to son's marijuana use. Four hundred three female college students and their fathers took part in the study. Results

Judith S. Brook; Martin Whiteman; Ann S. Gordon; David W. Brook

1984-01-01

269

Breath-holding in a marijuana smoker  

PubMed Central

It is vital to ask about illicit drug smoking in the respiratory history as marijuana smoking augments the detrimental effects of tobacco. We describe the case of a 28 year old marijuana smoker who developed a pneumothorax during a breath-holding competition. Pneumothorax is a common clinical entity that every physician should be aware of how to manage and lifetime risk is considerably increased by smoking and in exposure to barotrauma.

Aujayeb, Avinash; Donald, Calum; Doe, Simon

2011-01-01

270

Expectancies and marijuana use frequency and severity among young females.  

PubMed

This study examined associations between the endorsement of drug use expectancies and the frequency and severity of marijuana use in a community sample of 332 women aged 18-24years who were not explicitly seeking treatment for their marijuana use. Participants were enrolled in a larger intervention study of motivational interviewing for various health behaviors and provided self-reports of their current and past marijuana use, marijuana abuse/dependence symptoms, and marijuana use expectancies. Marijuana use expectancies were measured using the six subscales of the Marijuana Effects Expectancy Questionnaire (MEEQ). Use frequency was defined as the number of use days in the past month, severity as the total number of DSM-IV marijuana abuse or dependence symptom criteria met. Replicating and extending prior research, expectations regarding Relaxation and Tension Reduction emerged as a robust belief in this cohort, predicting not only frequency (p<.01) but also severity (p<.01) of marijuana use in multivariate analyses. Severity of marijuana use was further predicted by expectations regarding loss of control, affective changes following marijuana use, and other aspects of emotion dysregulation (Global Negative Effects, p<.01). These findings document meaningful associations between substance-related cognitions and use behavior and suggest that marijuana users who hold certain beliefs regarding marijuana use may be particularly susceptible to clinically significant problems associated with their substance use. As such, marijuana use expectancies may represent a clinical target that could be incorporated into future interventions. PMID:20621423

Hayaki, Jumi; Hagerty, Claire E; Herman, Debra S; de Dios, Marcel A; Anderson, Bradley J; Stein, Michael D

2010-11-01

271

From cannabis to the endocannabinoid system: refocussing attention on potential clinical benefits.  

PubMed

Cannabis sativa is one of the oldest herbal remedies known to man. Over the past four thousand years, it has been used for the treatment of numerous diseases but due to its psychoactive properties, its current medicinal usage is highly restricted. In this review, we seek to highlight advances made over the last forty years in the understanding of the mechanisms responsible for the effects of cannabis on the human body and how these can potentially be utilized in clinical practice. During this time, the primary active ingredients in cannabis have been isolated, specific cannabinoid receptors have been discovered and at least five endogenous cannabinoid neurotransmitters (endocannabinoids) have been identified. Together, these form the framework of a complex endocannabinoid signalling system that has widespread distribution in the body and plays a role in regulating numerous physiological processes within the body. Cannabinoid ligands are therefore thought to display considerable therapeutic potential and the drive to develop compounds that can be targeted to specific neuronal systems at low enough doses so as to eliminate cognitive side effects remains the 'holy grail' of endocannabinoid research. PMID:23155985

Youssef, F F; Irving, A J

2012-06-01

272

Marijuana use, driving, and related cognitions.  

PubMed

The purpose of the present study was to examine cognitive risk factors for driving after use of marijuana. We tested whether marijuana outcome expectancies and specific cognitions about driving after marijuana use were uniquely associated with the likelihood and frequency of driving while high (DWH) and riding with a high driver (RWHD). Participants were college students recruited from introductory psychology classes at a Midwestern university who reported ever using marijuana in their lifetime and reported having access to a car or driving at least once a month (n = 506). Greater perceived dangerousness of DWH was associated with decreased likelihood of DWH and RWHD. Negative marijuana expectancies were associated with decreased likelihood of DWH, and social norms were associated with decreased likelihood of RWHD. All cognitive predictors were associated with decreased frequency of DWH and RWHD for individuals with the propensity to engage in these behaviors. Findings suggest interventions to reduce risk of DWH and RWHD may benefit from targeting general expectancies about the negative effects of marijuana. Similarly, results suggest increasing students' knowledge of the potential danger of DWH may help to reduce the likelihood and frequency of DWH and RWHD. PMID:23276319

Arterberry, Brooke J; Treloar, Hayley R; Smith, Ashley E; Martens, Matthew P; Pedersen, Sarah L; McCarthy, Denis M

2013-09-01

273

Marijuana Use, Driving, and Related Cognitions  

PubMed Central

Objective The purpose of the present study was to examine cognitive risk factors for driving after use of marijuana. We tested whether marijuana outcome expectancies and specific cognitions about driving after marijuana use were uniquely associated with the likelihood and frequency of driving while high (DWH) and riding with a high driver (RWHD). Method Participants were college students recruited from introductory psychology classes at a Midwestern university who reported ever using marijuana in their lifetime and reported having access to a car or driving at least once a month (n = 506). Results Greater perceived dangerousness of DWH was associated with decreased likelihood of DWH and RWHD. Negative marijuana expectancies were associated with decreased likelihood of DWH, and social norms were associated with decreased likelihood of RWHD. All cognitive predictors were associated with decreased frequency of DWH and RWHD for individuals with the propensity to engage in these behaviors. Conclusions Findings suggest interventions to reduce risk of DWH and RWHD may benefit from targeting general expectancies about the negative effects of marijuana. Similarly, results suggest increasing students' knowledge of the potential danger of DWH may help to reduce the likelihood of and frequency of DWH and RWHD. PMID:23276319

Arterberry, Brooke J.; Treloar, Hayley R.; Smith, Ashley E.; Martens, Matthew P.; Pedersen, Sarah; McCarthy, Denis M.

2014-01-01

274

Marijuana and tobacco: a major connection?  

PubMed

Smoking among teens and college students is a significant public health challenge. Tobacco, marijuana, and alcohol continue to be the most commonly abused drugs by teens and young adults. Educational efforts have resulted in increased awareness of the mortality and morbidity attributed to smoking, second-hand smoke, and prenatal exposure to tobacco. Short- and long-term consequences of marijuana use are well documented in the literature, but they have received less wide spread attention. Even less well known is the relationship between these substances. Does use of one lead to use of the other? Are there synergistic and/or antagonistic effects when these substances are used together? We need answers to these questions to understand the prevalence of use and the impact of these drugs on our nations youth and young adults. The gateway theory of drug use is often used to describe the progression from using alcohol or tobacco, to marijuana, and later use of other drugs like MDMA, cocaine, and heroin. While tobacco use does commonly precede marijuana use, we propose that marijuana may be a "gateway drug" to tobacco smoking. Our research with university students is suggesting that cigarette-smoking initiation often follows or coincides with marijuana. PMID:14621344

Tullis, Laura Michelle; Dupont, Robert; Frost-Pineda, Kimberly; Gold, Mark S

2003-01-01

275

Cannabis use motives and personality risk factors.  

PubMed

According to the model of substance abuse of Conrod, Pihl, Stewart, and Dongier (2000), four personality factors (i.e., anxiety sensitivity [AS], introversion/hopelessness [I/H], sensation seeking [SS], and impulsivity [IMP]) are associated with elevated risk for substance use/misuse, with each personality factor being related to preference for particular drugs of abuse (e.g., AS with anxiolytics). However, cannabis use has not been consistently linked to any one of these personality factors. This may be due to the heterogeneity in cannabis use motives. The present study explored the association between these four personality risk factors and different cannabis use motives. Cannabis users completed an interview about their motives for cannabis use as well as the self-report Substance Use Risk Profile Scale (SURPS; Woicik, Conrod, Stewart, & Pihl, 2009), which measures the four personality risk factors. Results showed that AS was associated with conformity motives and I/H was associated with coping motives for cannabis use. SS was positively associated with expansion motives and IMP was associated with drug availability motives. Thus, personality risk factors in the model of Conrod et al. (2000) are associated with distinct cannabis use motives in a pattern consistent with theory. PMID:24368004

Hecimovic, Karen; Barrett, Sean P; Darredeau, Christine; Stewart, Sherry H

2014-03-01

276

Assessing topographical orientation skills in cannabis users.  

PubMed

The long-term effects of cannabis on human cognition are still unclear, but, considering that cannabis is a widely used substance and, overall, its potential use in therapeutic interventions, it is important to evaluate them. We hypothesize that the discrepancies among studies could be attributed to the specific cognitive function investigated and that skills subserved by the hippocampus, such as the spatial orientation abilities and, specifically, the ability to form and use cognitive maps, should be more compromised than others. Indeed it has been showed that cannabis users have a reduced hippocampus and that the hippocampus is the brain region in which cannabis has the greatest effect since it contains the highest concentration of cannabinoid receptors. To test this hypothesis we asked 15 heavy cannabis users and 19 nonusers to perform a virtual navigational test, the CMT, that assesses the ability to form and use cognitive maps. We found that using cannabis has no effect on these hippocampus-dependent orientation skills. We discuss the implications of our findings and how they relate to evidence reported in the literature that the intervention of functional reorganization mechanisms in cannabis user allows them to cope with the cognitive demands of navigational tasks. PMID:22272167

Palermo, Liana; Bianchini, Filippo; Iaria, Giuseppe; Tanzilli, Antonio; Guariglia, Cecilia

2012-01-01

277

Therapeutic use of cannabis: clarifying the debate.  

PubMed

The debate regarding therapeutic use of cannabis is being confused by a lack of distinction between therapeutic and social use of cannabis. Separate consideration of therapeutic and social use would enable strategies to minimise any negative social impact of therapeutic use. For therapeutic use of cannabis to be considered on its own merits, greater emphasis needs to be placed on scientific evidence of therapeutic efficacy. At present the evidence is limited, it mostly relates to the use of synthetic cannabinoids, and much of it fails to compare cannabis with the best therapies available for the conditions of interest. Claims of therapeutic efficacy tend to be based on opinion and anecdote rather than the results of controlled studies. Further research is needed to clarify the potential therapeutic benefits, to enable claims of therapeutic use to be objectively assessed and to enable informed decisions to be made about the relative risks and benefits for any individual using cannabis for therapeutic purposes. Further research is required to clarify the efficacy of pure, synthetic cannabinoids compared to cannabis, the most effective route of administration, and the importance of delivering a known dose. The most likely value of cannabis is as an adjunct, rather than a replacement for, current medical approaches. The potential therapeutic benefits of cannabis will be greatest for those conditions where long-term cannabis use, with its attendant health risks, is not an issue and where the patient has the capacity to titrate dose against symptoms. There is sufficient evidence of potential therapeutic benefit to justify the facilitation of further research. PMID:16203511

Gowing, L R; Ali, R L; Christie, P; White, J M

1998-12-01

278

Validation of the Cannabis Abuse Screening Test in a Sample of Cannabis Inpatients  

Microsoft Academic Search

The present study aims at validating the Cannabis Abuse Screening Test (CAST) in a clinical sample of adolescent and young adult cannabis users seeking treatment. Applying a classical test theory approach using DSM-IV diagnoses as gold standard, two versions of the CAST questionnaire are compared. The sample consisted of 140 subjects aged 15–26 years (mean 18.9) recruited from two cannabis

Stéphane Legleye; Ludwig Kraus; Daniela Piontek; Olivier Phan; Céline Jouanne

2012-01-01

279

Cannabis use, schizotypy and personality : associations with cannabis-related problems and emotion recognition.  

E-print Network

??Individuals with schizotypy often report more cannabis-related problems, which include cognitive, interpersonal, and social responsibility difficulties. Past studies have observed correlations between the factors of… (more)

Blanchard, Brittany Elizabeth

2013-01-01

280

Effectiveness of a Marijuana Expectancy Manipulation: Piloting the Balanced-Placebo Design for Marijuana  

PubMed Central

Although alcohol and nicotine administration studies have demonstrated that manipulating subjects’ expectancies regarding drug content affects drug response, research with marijuana has not adequately studied drug expectancy effects. The present pilot study was the first to evaluate the credibility and effect of expectancy manipulation on subjective measures and smoking patterns using a marijuana administration balanced-placebo design (BPD). In a 2 × 2 instructional set (told delta-9-tetrahydrocannabinol [THC] vs. told no THC) by drug (smoked marijuana with 2.8% THC vs. placebo) between-subjects design, the authors examined the effect of marijuana expectancy manipulation and the pharmacologic effect on affective and physiologic measures, cigarette ratings, and smoking behavior with 20 marijuana smokers (mean age = 20 years; 25% female). Large main effects of expectancy were found on ratings of cigarette potency, strength, taste, smell, and satisfaction, and observed smoking behavior. Pharmacologic effects were particularly evident for self-reported physical reactions to marijuana and cigarette potency and satisfaction ratings. This study demonstrated the feasibility of the BPD research with marijuana and yielded promising results for future studies examining the independent and combined effects of marijuana pharmacology and expectancies. PMID:19653787

Metrik, Jane; Rohsenow, Damaris J.; Monti, Peter M.; McGeary, John; Cook, Travis A. R.; de Wit, Harriet; Haney, Margaret; Kahler, Christopher W.

2009-01-01

281

Subjective effects to marijuana associated with marijuana use in community and clinical subjects  

Microsoft Academic Search

IntroductionMarijuana is the most commonly used illicit drug among adolescents. Marijuana use induces both psychological and physiological responses, which can be interpreted by an individual in a variety of ways (i.e. subjective effects). We have examined subjective effects in adolescent, young adult community, and clinical populations to determine how patterns of use may be predicted by an individual's subjective experiences

Joanna S. Zeiger; Brett C. Haberstick; Robin P. Corley; Marissa A. Ehringer; Thomas J. Crowley; John K. Hewitt; Christian J. Hopfer; Michael C. Stallings; Susan E. Young; Soo Hyun Rhee

2010-01-01

282

Coping and Self-Efficacy in Marijuana Treatment: Results from the Marijuana Treatment Project  

ERIC Educational Resources Information Center

This study examined whether a coping-skills-based treatment for marijuana dependence operated by encouraging the use of coping skills or via other mechanisms. Participants were 450 men and women treated in the multisite Marijuana Treatment Project who were randomly assigned to motivational enhancement therapy plus cognitive-behavioral (MET-CB)…

Litt, Mark D.; Kadden, Ronald M.; Stephens, Robert S.

2005-01-01

283

Effectiveness of a marijuana expectancy manipulation: Piloting the balanced-placebo design for marijuana.  

PubMed

Although alcohol and nicotine administration studies have demonstrated that manipulating subjects' expectancies regarding drug content affects drug response, research with marijuana has not adequately studied drug expectancy effects. The present pilot study was the first to evaluate the credibility and effect of expectancy manipulation on subjective measures and smoking patterns using a marijuana administration balanced-placebo design (BPD). In a 2 x 2 instructional set (told delta-9-tetrahydrocannabinol [THC] vs. told no THC) by drug (smoked marijuana with 2.8% THC vs. placebo) between-subjects design, the authors examined the effect of marijuana expectancy manipulation and the pharmacologic effect on affective and physiologic measures, cigarette ratings, and smoking behavior with 20 marijuana smokers (mean age = 20 years; 25% female). Large main effects of expectancy were found on ratings of cigarette potency, strength, taste, smell, and satisfaction, and observed smoking behavior. Pharmacologic effects were particularly evident for self-reported physical reactions to marijuana and cigarette potency and satisfaction ratings. This study demonstrated the feasibility of the BPD research with marijuana and yielded promising results for future studies examining the independent and combined effects of marijuana pharmacology and expectancies. PMID:19653787

Metrik, Jane; Rohsenow, Damaris J; Monti, Peter M; McGeary, John; Cook, Travis A R; de Wit, Harriet; Haney, Margaret; Kahler, Christopher W

2009-08-01

284

Marijuana withdrawal and aggression among a representative sample of U.S. marijuana users  

PubMed Central

Background Previous laboratory-based research suggests that withdrawal from marijuana may cause increased aggression. It is unclear whether this finding extends beyond the laboratory setting to the general population of marijuana users. The purpose of this study was to test a cross-sectional association between marijuana withdrawal symptoms and aggression among a representative sample of U.S. adult marijuana users, and to test whether this association was moderated by previous history of aggression. Methods Data were analyzed from the National Epidemiologic Survey on Alcohol and Related Conditions. Wave Two data (2004–2005) were used for all variables except for history of aggression, which was assessed during the Wave One interview (2001–2002). Two outcomes were examined: self-report general aggression and relationship aggression. Odds ratios for aggression based on withdrawal symptoms and the interaction between withdrawal symptoms and history of aggression were calculated using logistic regression, adjusting for covariates and accounting for the complex survey design. Results Among marijuana users with a history of aggression, marijuana withdrawal was associated with approximately 60% higher odds of past year relationship aggression (p < 0.05). There was no association between withdrawal symptoms and relationship aggression among those without a history of aggression, and no association with general aggression regardless of history of aggression. Conclusions The findings from this study support the notion that laboratory-based increases in aggression due to marijuana withdrawal extend to the general population of marijuana users who have a previous history of aggression. PMID:23380439

Smith, Philip H.; Homish, Gregory G.; Leonard, Kenneth E.; Collins, R. Lorraine

2013-01-01

285

Persistent cannabis users show neuropsychological decline from childhood to midlife.  

PubMed

Recent reports show that fewer adolescents believe that regular cannabis use is harmful to health. Concomitantly, adolescents are initiating cannabis use at younger ages, and more adolescents are using cannabis on a daily basis. The purpose of the present study was to test the association between persistent cannabis use and neuropsychological decline and determine whether decline is concentrated among adolescent-onset cannabis users. Participants were members of the Dunedin Study, a prospective study of a birth cohort of 1,037 individuals followed from birth (1972/1973) to age 38 y. Cannabis use was ascertained in interviews at ages 18, 21, 26, 32, and 38 y. Neuropsychological testing was conducted at age 13 y, before initiation of cannabis use, and again at age 38 y, after a pattern of persistent cannabis use had developed. Persistent cannabis use was associated with neuropsychological decline broadly across domains of functioning, even after controlling for years of education. Informants also reported noticing more cognitive problems for persistent cannabis users. Impairment was concentrated among adolescent-onset cannabis users, with more persistent use associated with greater decline. Further, cessation of cannabis use did not fully restore neuropsychological functioning among adolescent-onset cannabis users. Findings are suggestive of a neurotoxic effect of cannabis on the adolescent brain and highlight the importance of prevention and policy efforts targeting adolescents. PMID:22927402

Meier, Madeline H; Caspi, Avshalom; Ambler, Antony; Harrington, HonaLee; Houts, Renate; Keefe, Richard S E; McDonald, Kay; Ward, Aimee; Poulton, Richie; Moffitt, Terrie E

2012-10-01

286

Medical Marijuana | NSW May Legalise Medical Marijuana http://www.smh.com.au/opinion/politics/medical-marijuana-a-sensible-step-back-from-past-paranoia-20130204-2dudm.html[5/02/2013 11:08:13 AM  

E-print Network

Medical Marijuana | NSW May Legalise Medical Marijuana http://www.smh.com.au/opinion/politics/medical-marijuana Beatrix and bring in new 331 Blogs Medical marijuana a sensible step back from past paranoia Home National Contributors Editorials Blogs CartoonsPolitical Opinion More Search #12;Medical Marijuana | NSW May Legalise

287

Comparison of the analgesic effects of dronabinol and smoked marijuana in daily marijuana smokers.  

PubMed

Recent studies have demonstrated the therapeutic potential of cannabinoids to treat pain, yet none have compared the analgesic effectiveness of smoked marijuana to orally administered ?(9)-tetrahydrocannabinol (THC; dronabinol). This randomized, placebo-controlled, double-dummy, double-blind study compared the magnitude and duration of analgesic effects of smoked marijuana and dronabinol under well-controlled conditions using a validated experimental model of pain. Healthy male (N=15) and female (N=15) daily marijuana smokers participated in this outpatient study comparing the analgesic, subjective, and physiological effects of marijuana (0.00, 1.98, or 3.56% THC) to dronabinol (0, 10, or 20?mg). Pain response was assessed using the cold-pressor test (CPT): participants immersed their left hand in cold water (4?°C), and the time to report pain (pain sensitivity) and withdraw the hand from the water (pain tolerance) were recorded. Subjective pain and drug effect ratings were also measured as well as cardiovascular effects. Compared with placebo, marijuana and dronabinol decreased pain sensitivity (3.56%; 20?mg), increased pain tolerance (1.98%; 20?mg), and decreased subjective ratings of pain intensity (1.98, 3.56%; 20?mg). The magnitude of peak change in pain sensitivity and tolerance did not differ between marijuana and dronabinol, although dronabinol produced analgesia that was of a longer duration. Marijuana (1.98, 3.56%) and dronabinol (20?mg) also increased abuse-related subjective ratings relative to placebo; these ratings were greater with marijuana. These data indicate that under controlled conditions, marijuana and dronabinol decreased pain, with dronabinol producing longer-lasting decreases in pain sensitivity and lower ratings of abuse-related subjective effects than marijuana. PMID:23609132

Cooper, Ziva D; Comer, Sandra D; Haney, Margaret

2013-09-01

288

Cannabis Use and Psychosis: A Review of Clinical and Epidemiological Evidence?  

Microsoft Academic Search

Objective: This paper evaluates evidence for two hypotheses about the relationship between cannabis use and psychosis: (i) that heavy cannabis use causes a ‘cannabis psychosis’, i.e. a psychotic disorder that would not have occurred in the absence of cannabis use and which can be recognised by its pattern of symptoms and their relationship to cannabis use; and (ii) that cannabis

Wayne Hall; Louisa Degenhardt

2000-01-01

289

Approach to cannabis use disorder in primary care  

PubMed Central

Objective To review the clinical features and complications of at-risk cannabis use and cannabis use disorder, and to outline an office-based protocol for screening, identifying, and managing this disorder. Sources of information PubMed was searched for controlled trials, observational studies, and reviews on cannabis use among adolescents and young adults; cannabis-related medical and psychiatric harms; cannabis use disorder and its treatment; and lower-risk cannabis use guidelines. Main message Physicians should ask all patients about cannabis use. They should ask adolescents and young adults and those at highest risk of cannabis-related harms (those with concurrent psychiatric or substance use disorders) more frequently. Physicians should also ask about cannabis use in patients who have problems that could be caused by cannabis, such as mood disorders, psychosis, and respiratory symptoms. In patients who report cannabis use, physicians should inquire about frequency and amount, tolerance and withdrawal symptoms, attempts to reduce use, and cannabis-related harms. Lower-risk cannabis users smoke, inhale, or ingest cannabis occasionally without evidence of school, work, or social dysfunction; those with problematic use often use cannabis daily or almost daily, have difficulty reducing their use, and have impaired school, work, or social functioning. Physicians should offer all patients with problematic use brief advice and counseling, focusing on the health effects of cannabis and setting a goal of abstinence (some higher-risk groups should not use cannabis at all) or reduced use, and they should provide practical strategies to reduce cannabis use. Physicians should incorporate simple motivational interviewing techniques into the counseling sessions. They should refer those patients who are unable to reduce use or who are experiencing harms from cannabis use to specialized care, while ensuring those patients remain connected to primary care. As well, physicians should give information on lower-risk cannabis use to all cannabis users. Conclusion Physicians should screen all patients in their practices at least once for cannabis use, especially those who have problems that might be caused by cannabis. Physicians should screen those at higher risk more often, at least annually. Lower-risk cannabis use should be distinguished from problematic use. Brief counseling should be provided to those with problematic use; these patients should be referred to specialists if they are unable to reduce or cease use. PMID:25217674

Turner, Suzanne D.; Spithoff, Sheryl; Kahan, Meldon

2014-01-01

290

Metabolic Effects of Chronic Cannabis Smoking  

PubMed Central

OBJECTIVE We examined if chronic cannabis smoking is associated with hepatic steatosis, insulin resistance, reduced ?-cell function, or dyslipidemia in healthy individuals. RESEARCH DESIGN AND METHODS In a cross-sectional, case-control study, we studied cannabis smokers (n = 30; women, 12; men, 18; 27 ± 8 years) and control subjects (n = 30) matched for age, sex, ethnicity, and BMI (27 ± 6). Abdominal fat depots and intrahepatic fat content were quantified by magnetic resonance imaging and proton magnetic resonance spectroscopy, respectively. Insulin-sensitivity indices and various aspects of ?-cell function were derived from oral glucose tolerance tests (OGTT). RESULTS Self-reported cannabis use was: 9.5 (2–38) years; joints/day: 6 (3–30) [median (range)]. Carbohydrate intake and percent calories from carbohydrates, but not total energy intake, were significantly higher in cannabis smokers. There were no group differences in percent total body fat, or hepatic fat, but cannabis smokers had a higher percent abdominal visceral fat (18 ± 9 vs. 12 ± 5%; P = 0.004). Cannabis smokers had lower plasma HDL cholesterol (49 ± 14 vs. 55 ± 13 mg/dL; P = 0.02), but fasting levels of glucose, insulin, total cholesterol, LDL cholesterol, triglycerides, or free fatty acids (FFA) were not different. Adipocyte insulin resistance index and percent FFA suppression during an OGTT was lower (P < 0.05) in cannabis smokers. However, oral glucose insulin sensitivity index, measures of ?-cell function, or incretin concentrations did not differ between the groups. CONCLUSIONS Chronic cannabis smoking was associated with visceral adiposity and adipose tissue insulin resistance but not with hepatic steatosis, insulin insensitivity, impaired pancreatic ?-cell function, or glucose intolerance. PMID:23530011

Muniyappa, Ranganath; Sable, Sara; Ouwerkerk, Ronald; Mari, Andrea; Gharib, Ahmed M.; Walter, Mary; Courville, Amber; Hall, Gail; Chen, Kong Y.; Volkow, Nora D.; Kunos, George; Huestis, Marilyn A.; Skarulis, Monica C.

2013-01-01

291

Is cannabis a gateway to hard drugs?  

Microsoft Academic Search

The gateway hypothesis proposes that use of cannabis directly increases the risk of consuming hard drugs. We test this controversial,\\u000a but influential, hypothesis on a sample of cannabis users, exploiting a unique set of drug price data. A flexible approach\\u000a is developed to identify the causal gateway effect using a bivariate survival model with shared frailty estimated using a\\u000a latent

Hans Olav Melberg; Andrew M. Jones; Anne Line Bretteville-Jensen

2010-01-01

292

EEG of Chronic Marijuana Users during Abstinence: Relationship to Years of Marijuana Use, Cerebral Blood Flow and Thyroid Function  

PubMed Central

Objective Marijuana abuse is associated with neurological changes including increases in frontal EEG alpha during abstinence. Research is needed to assess to what extent these EEG patterns are indicative of cerebral perfusion deficits. Methods We recorded the resting eyes closed EEG of 75 abstinent marijuana users and 33 control subjects. Fifty-six marijuana users used marijuana for less than eight years and 19 used for eight years or more. The EEG evaluation occurred within 72 hours of admission to an inpatient unit. Fifty-nine marijuana users remained abstinent for a month and were tested twice. Supplemental psychological and physiological data were also collected. Results Log alpha2 and beta2 power at posterior sites were significantly lower for the marijuana abusers that used eight years or more than the other marijuana abusers and the control subjects. These EEG changes continued for the month of abstinence. The marijuana users who used marijuana for more than eight years, also, had lower heart rates and thyroid function (T4) compared to the other marijuana users and the control subjects. Conclusions Chronic marijuana use was also associated with reduced EEG power in alpha and beta bands at posterior sites. These reductions in EEG power appear to be related to cerebral perfusion deficits and/or thyroid function in marijuana abusers. Significance Our results suggest EEG, cerebral blood flow velocity, cardiovascular and thyroid function alterations in marijuana abuser with an extended period of use. These alterations reflect under arousal in these systems. PMID:18065267

Herning, Ronald I.; Better, Warren; Cadet, Jean L.

2008-01-01

293

A human laboratory study investigating the effects of quetiapine on marijuana withdrawal and relapse in daily marijuana smokers.  

PubMed

Marijuana withdrawal contributes to the high relapse rates in individuals seeking treatment for marijuana-use disorders. Quetiapine, an atypical antipsychotic, reduces characteristic symptoms of marijuana withdrawal in a variety of psychiatric conditions, including mood lability, sleep disruption and anorexia. This human laboratory study investigated the effectiveness of quetiapine to decrease marijuana withdrawal and relapse to marijuana use in non-treatment-seeking marijuana smokers. Volunteers were maintained on placebo or quetiapine (200?mg/day) in this double-blind, counter-balanced, within-subject study consisting of two 15-day medication phases, the last 8 days of which were in-patient. On the first in-patient day, active marijuana [6.2% delta (9)-tetrahydrocannabinol (THC)] was repeatedly smoked under controlled conditions. For the next 3 days, inactive marijuana (0.0% THC) was available for self-administration (withdrawal). On the subsequent 4 days, active marijuana (6.2% THC) was available for self-administration (relapse). Volunteers (n?=?14) who smoked an average of 10 marijuana cigarettes/day, 7 days/week, completed the study. Under placebo, withdrawal was marked by increased subjective ratings of negative mood, decreased sleep quality, and decreased caloric intake and weight loss. Compared with placebo, quetiapine improved sleep quality, increased caloric intake and decreased weight loss. However, quetiapine increased marijuana craving and marijuana self-administration during the relapse phase. These data do not suggest that quetiapine shows promise as a potential treatment for marijuana dependence. PMID:22741619

Cooper, Ziva D; Foltin, Richard W; Hart, Carl L; Vosburg, Suzanne K; Comer, Sandra D; Haney, Margaret

2013-11-01

294

Concurrence chez Vicia sativa L et Avena sativa L. II. Effets des contraintes hydriques et nutritionnelles  

E-print Network

Agronomie Concurrence chez Vicia sativa L et Avena sativa L. II. Effets des contraintes hydriques Summary ― Competition in Vicia sativa L and Avena sativa L. II. Effects of water and nutritional

Paris-Sud XI, Université de

295

Concurrence chez Vicia sativa L et Avena sativa L. I. Effets des contraintes hydriques et nutritionnelles  

E-print Network

Agronomie Concurrence chez Vicia sativa L et Avena sativa L. I. Effets des contraintes hydriques et / morphogenèse / concurrence Summary — Competition in Vicia sativa L and Avena sativa L.I. Effects of water

Paris-Sud XI, Université de

296

Fewer Painkiller Deaths in States with Medical Marijuana  

MedlinePLUS

... enable JavaScript. Fewer Painkiller Deaths in States With Medical Marijuana: Study People with chronic pain may use pot ... 25, 2014 (HealthDay News) -- States that have legalized medical marijuana tend to experience an unexpected benefit -- fewer overdose ...

297

Delay Discounting in Current and Former Marijuana-Dependent Individuals  

Microsoft Academic Search

Studies have found that a variety of drug-dependent groups discount delayed rewards more than matched controls. This study compared delay discounting for a hypothetical $1,000 reward among dependent marijuana users, former dependent marijuana users, and matched controls. Discounting of marijuana was also assessed in the currently marijuana-dependent group. No significant differences in discounting were detected among the groups; however, currently

Matthew W. Johnson; Warren K. Bickel; Forest Baker; Brent A. Moore; Gary J. Badger; Alan J. Budney

2010-01-01

298

House votes 310-93 to reject marijuana as medicine.  

PubMed

House resolution H.J. Res.117 discourages the use of marijuana for medicinal purposes and supports enforcement of current Federal drug laws. The resolution clearly states that the benefits of marijuana are unclear. Several states have put forth initiatives to approve the use of marijuana for individuals who have serious or terminal conditions. Further research on the medical use of marijuana is being conducted by the National Academy of Sciences. PMID:11365938

1998-10-01

299

Cannabis Reclassification: What Is the Message to the Next Generation of Cannabis Users?  

ERIC Educational Resources Information Center

At the beginning of 2004 the UK government downgraded the legal status of cannabis from a Class B to a Class C drug. Following a review of this decision two years later, cannabis remained a Class C substance--which for some contrasted with the potential harmful social and health effects associated with its use, particularly for young people. These…

McCrystal, Patrick; Winning, Kerry

2009-01-01

300

The Marijuana Ladder: Measuring motivation to change marijuana use in incarcerated adolescents  

PubMed Central

The purpose of this study was to determine if a modified version of the Contemplation Ladder, a measure of motivation to change marijuana use among incarcerated adolescents (Marijuana Ladder; ML), was related to marijuana use and treatment engagement. Participants (N = 122) in this study were all incarcerated at a state juvenile correctional facility in the Northeast. Adolescents were assessed at the beginning of their incarceration, 2 months into their incarceration, and 3 months after their release. There was a significant negative relationship between ML scores and marijuana use and a significant positive relationship between ML scores and treatment engagement. When controlling for prior marijuana use and age, ML scores at baseline significantly added to the prediction of marijuana use and treatment engagement among incarcerated adolescents. Results support the concurrent validity and the predictive validity of the ML. This measure has the potential to provide important information for Juvenile Justice Facilities that might aid in treatment planning and discharge planning for incarcerated adolescents. In addition, researchers may find a quick visual analog measure of motivation to change marijuana use with good psychometric properties useful. PMID:16289930

Slavet, James D.; Stein, L.A.R.; Colby, Suzanne M.; Barnett, Nancy P.; Monti, Peter M.; Golembeske, Charles; Lebeau-Craven, Rebecca

2009-01-01

301

Marijuana and Related Drug Consumption in Australia - Some Microeconometrics Evidence  

Microsoft Academic Search

This paper presents some econometric analysis on Australian individuals' consumption of marijuana and related drugs using unit record data from the National Drug Strategy Household Survey. We investigate the effects of individual socioeconomic and demographic factors and drug prices on participation probability and levels of marijuana consumption. We use multivariate probit models to study the relationship of marijuana participation with

Xueyan Zhao

2007-01-01

302

Medical marijuana and the developing role of the pharmacist  

Microsoft Academic Search

Purpose. The pharmacology, therapeutic uses, safety, drug-drug interactions, and drug-disease interactions of medical mari- juana are reviewed, and the legal issues related to its use and the implications of medical marijuana for the pharmacist are presented. Summary. Marijuana contains more than 460 active chemicals and over 60 unique cannabinoids. The legal landscape sur- rounding marijuana is surprisingly complex and unsettled.

MATTHEW J. SEAMON; JENNIFER A. FASS; MARIA MANISCALCO-FEICHTL; NADA A. ABU-SHRAIE

2007-01-01

303

Medical Marijuana Use among Adolescents in Substance Abuse Treatment  

ERIC Educational Resources Information Center

Objective: To assess the prevalence and frequency of medical marijuana diversion and use among adolescents in substance abuse treatment and to identify factors related to their medical marijuana use. Method: This study calculated the prevalence and frequency of diverted medical marijuana use among adolescents (n = 164), ages 14-18 years (mean age…

Salomonsen-Sautel, Stacy; Sakai, Joseph T.; Thurstone, Christian; Corley, Robin; Hopfer, Christian

2012-01-01

304

Delay Discounting in Current and Former Marijuana-Dependent Individuals  

PubMed Central

Studies have found that a variety of drug dependent groups discount delayed rewards more than matched-controls. This study compared delay discounting for a hypothetical $1000 reward among dependent marijuana users, former dependent marijuana users, and matched-controls. Discounting of marijuana was also assessed in the currently marijuana-dependent group. No significant difference in discounting was detected among the groups, however currently dependent users showed a trend to discount money more than the other two groups. Within the dependent marijuana group, marijuana was discounted more than money, and discounting for money and marijuana were significantly and positively correlated. Regression analyses indicated that delay discounting was more closely associated with tobacco use than marijuana use. A variety of questionnaires were also administered, including impulsivity questionnaires. Dependent marijuana users scored as significantly more impulsive on the Impulsiveness subscale of the Eysenck Impulsiveness-Venturesomeness-Empathy questionnaire than controls. However, the three groups did not significantly differ on several other personality questionnaires including the Barratt Impulsivity Scale-11. The Stanford Time Perception Inventory Present-Fatalistic subscale was positively correlated with money and marijuana discounting, indicating that a greater sense of powerlessness over the future is related to greater delay discounting. Results suggest that current marijuana dependence may be associated with a trend toward increased delay discounting, but this effect size appears to be smaller for marijuana than for previously examined drugs. PMID:20158299

Bickel, Warren K.; Baker, Forest; Moore, Brent A.; Badger, Gary J.; Budney, Alan J.

2010-01-01

305

Delay discounting in current and former marijuana-dependent individuals.  

PubMed

Studies have found that a variety of drug-dependent groups discount delayed rewards more than matched controls. This study compared delay discounting for a hypothetical $1,000 reward among dependent marijuana users, former dependent marijuana users, and matched controls. Discounting of marijuana was also assessed in the currently marijuana-dependent group. No significant differences in discounting were detected among the groups; however, currently dependent users showed a trend to discount money more than the other 2 groups. Within the dependent marijuana group, marijuana was discounted more than money, and discounting for money and marijuana was significantly and positively correlated. Regression analyses indicated that delay discounting was more closely associated with tobacco use than marijuana use. A variety of questionnaires were also administered, including impulsivity questionnaires. Dependent marijuana users scored as significantly more impulsive on the Impulsiveness subscale of the Eysenck Impulsiveness-Venturesomeness-Empathy questionnaire than controls. However, the 3 groups did not significantly differ on several other personality questionnaires, including the Barratt Impulsivity Scale-11. The Stanford Time Perception Inventory Present-Fatalistic subscale was positively correlated with money and marijuana discounting, indicating that a greater sense of powerlessness over the future is related to greater delay discounting. Results suggest that current marijuana dependence may be associated with a trend toward increased delay discounting, but this effect size appears to be smaller for marijuana than for previously examined drugs. PMID:20158299

Johnson, Matthew W; Bickel, Warren K; Baker, Forest; Moore, Brent A; Badger, Gary J; Budney, Alan J

2010-02-01

306

Epidemiologic review of marijuana use and cancer risk  

Microsoft Academic Search

Marijuana is the most commonly used illegal drug in the United States and is considered by young adults to be the illicit drug with the least risk. On the other hand, marijuana smoke contains several of the same carcinogens and co-carcinogens as the tar from tobacco, raising concerns that smoking of marijuana may be a risk factor for tobacco-related cancers.

Mia Hashibe; Kurt Straif; Donald P. Tashkin; Hal Morgenstern; Sander Greenland; Zuo-Feng Zhang

2005-01-01

307

Liberty Lost: The Moral Case for Marijuana Law Reform  

Microsoft Academic Search

Marijuana policy analyses typically focus on the relative costs and benefits of present policy and its feasible alternatives. This Essay addresses a prior, threshold issue: whether marijuana criminal laws abridge fundamental individual rights, and if so, whether there are grounds that justify doing so. Over 700, 000 people are arrested annually for simple marijuana possession, a small but significant proportion

Eric Blumenson; Eva Nilsen

2010-01-01

308

QUELS FUTURS TRAITEMENTS POUR LA DEPENDANCE AU TABAC ET AU CANNABIS?  

PubMed Central

RESUME Plus de trois millions de morts sont attribués au tabagisme dans le monde par an, et l’usage de tabac est en progression dans les pays en voie de développement. L’usage de tabac est donc une des rares causes de mortalité qui augmente, avec une prévision de plus de 10 millions de morts par an dans 30–40 ans. Le cannabis ou marijuana est la drogue illicite la plus consommée dans le monde et il n’y a actuellement pas de traitement disponible. Bien que les systèmes dopaminergiques jouent un rôle central dans les effets renforçants des drogues, d’autres systèmes sont impliqués. Nous présentons ici des résultats récents obtenus avec des antagonistes des récepteurs cannabinoides CB1, des récepteurs D3 de la dopamine et des récepteurs opioïdes. Ces antagonistes qui modulent de façon directe ou indirecte la transmission dopaminergique cérébrale représentent des approches prometteuses pour le traitement du tabagisme ou de la dépendance au cannabis. Ces approches sont à valider dans des essais cliniques. PMID:18663981

LE FOLL, Bernard; JUSTINOVA, Zuzana; TANDA, Gianlugi; GOLDBERG, Steven R.

2009-01-01

309

Synthesis and in vitro autoradiographic evaluation of a novel high-affinity radioiodinated ligand for imaging brain cannabinoid subtype-1 receptors  

E-print Network

of Mental Health, National Institutes of Health, Bethesda, MD 20892, USA b Karolinska Institutet, Department radioligand in non-human primate. Ã? 2009 Elsevier Ltd. All rights reserved. Cannabis sativa (marijuana) is one beneficial effects of cannabis intake may include anti-emesis and appetite stimulation. Conversely

Shen, Jun

310

Evaluation of [11 C]PipISB and [18  

E-print Network

Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda Wiley-Liss, Inc.y INTRODUCTION Cannabis sativa (marijuana) intake has long been known to elicit of a specific receptor class, the cannabi- noid receptors (i.e., CB1 and CB2) (Devane et al., 1988; Munro et al

Shen, Jun

311

Do Citizens Accurately Perceive Marijuana Sanction Risks? A Test of a Critial Assumption in Deterrence Theory and the Decriminalization Debate  

E-print Network

2003. Cannabis use and dependence: Public health and publicpolicies on cannabis consumption. 13 Health Economics 123-cannabis use among college students: Economic complements or substitutes? 13 Health

MacCoun, Robert; Pacula, Rosalie Liccardo; Chriqui, Jamie F; Harris, Katherine; Reuter, Peter H

2008-01-01

312

TECHNICAL NOTE Shannon L. Datwyler,1,2  

E-print Network

in Hemp and Marijuana (Cannabis sativa L.) According to Amplified Fragment Length PolymorphismsÃ? ABSTRACT cultivars have forensic utility, but no direct comparison of hemp and marijuana amplified fragment length polymorphism (AFLP) has been made to date. Genetic variation was surveyed in three populations of fiber hemp

Weiblen, George D

313

Investigating the interaction between schizotypy, divergent thinking and cannabis use  

PubMed Central

Cannabis acutely increases schizotypy and chronic use is associated with elevated rates of psychosis. Creative individuals have higher levels of schizotypy, however links between cannabis use, schizotypy and creativity have not been investigated. We investigated the effects of cannabis smoked naturalistically on schizotypy and divergent thinking, a measure of creativity. One hundred and sixty cannabis users were tested on 1 day when sober and another day when intoxicated with cannabis. State and trait measures of both schizotypy and creativity were administered. Quartile splits compared those lowest (n = 47) and highest (n = 43) in trait creativity. Cannabis increased verbal fluency in low creatives to the same level as that of high creatives. Cannabis increased state psychosis-like symptoms in both groups and the high creativity group were significantly higher in trait schizotypy, but this does not appear to be linked to the verbal fluency change. Acute cannabis use increases divergent thinking as indexed by verbal fluency in low creatives. PMID:22230356

Schafer, Grainne; Feilding, Amanda; Morgan, Celia J.A.; Agathangelou, Maria; Freeman, Tom P.; Valerie Curran, H.

2012-01-01

314

Using the bioecological model to predict risk perception of marijuana use and reported marijuana use in adolescence  

Microsoft Academic Search

PurposeThe purpose of the study was to investigate the ability of the Bioecological Model (BEM) to predict adolescents' risk perception (RP) of marijuana use and reported marijuana use. The secondary aim of the study was to investigate the extent to which the BEM influenced adolescents' decision-making regarding marijuana use by exploring the BEM's ability to moderate the relationship between adolescents'

Sasha A. Fleary; Robert W. Heffer; E. Lisako J. McKyer; Daniel A. Newman

2010-01-01

315

The Teen Marijuana Check-Up: An In-School Protocol for Eliciting Voluntary Self-Assessment of Marijuana Use  

Microsoft Academic Search

Given the prevalence of regular marijuana use among adolescents and the associated risks for adverse consequences to functioning, effective interventions are needed that are tailored to this population. To date, most such counseling approaches have relied on nonvoluntary participation by adolescent marijuana smokers and the outcomes have been only modestly successful. The Teen Marijuana Check-Up is a brief motivational enhancement

Megan Swan; Sam Schwartz; Belinda Berg; Denise Walker; Robert Stephens; Roger Roffman

2008-01-01

316

Voters in two States endorse medicinal marijuana.  

PubMed

Voters in California and Arizona decided that the medical use of marijuana should be legal and available to treat people with terminal illnesses, such as AIDS. These initiatives were opposed by both President Clinton and his challenger Bob Dole, and three former presidents warn that these measures will undermine drug prevention efforts. Law enforcement officials in both States campaigned against these initiatives. The measures do not change Federal laws, leaving physicians with a legal dilemma. If physicians prescribe marijuana, the Drug Enforcement Administration could investigate them and revoke their licenses to dispense prescriptions. PMID:11364055

1996-11-29

317

Small-Scale Cannabis Growers in Denmark and Finland  

Microsoft Academic Search

Aims: To compare domestic cannabis cultivation in Denmark and Finland to describe national characteristics in small-scale cannabis growing. Design: A Web survey conducted among small-scale cannabis growers in Denmark (June to November 2008) and Finland (May to June 2009). Participants: Current cannabis growers (Denmark, 401; Finland, 1,054). Measurements: Comparisons in regard to social background, growing history, practices, purposes and motives

Pekka Hakkarainen; Vibeke Asmussen Frank; Jussi Perälä; Helle Vibeke Dahl

2011-01-01

318

Jordanian adolescent cannabis use: Patterns, risks, and protective factors  

Microsoft Academic Search

Background. Cannabis is considered to be the most commonly used substances worldwide. Its use is not only common among adolescents but is increasing in developing countries such as Jordan. Cannabis use among adolescents has been linked to unintentional injuries, physical fights, academic problems, and illegal behavior such as driving under the influence. Studies of cannabis use patterns, risks, and protective

Sukaina Abd Al-Rhmman Alzyoud

2010-01-01

319

Infant with Altered Consciousness after Cannabis Passive Inhalation  

ERIC Educational Resources Information Center

We report on an infant who was admitted to hospital with severe neurological symptoms following passive inhalation of cannabis. To date, cannabis abuse has been described almost entirely in adolescents and adults. In early childhood, however, cannabis effects were almost exclusively discussed in the context of maternal prenatal exposure, and the…

Zarfin, Yehoshua; Yefet, Enav; Abozaid, Said; Nasser, Wael; Mor, Tamer; Finkelstein, Yoram

2012-01-01

320

The Effects of Cannabis Use on Physical and Mental Health  

Microsoft Academic Search

This paper investigates whether cannabis use affects physical and mental health. To do so, information on prime aged individuals living in Amsterdam in 1994 is used. Dutch data offer a clear advantage in estimating the health impacts of cannabis use because the legal status of cannabis in the Netherlands ensures that estimates are free from confounding with the physical and

Jan C van Ours; Jenny Williams

2011-01-01

321

The effects of cannabis use on physical and mental health  

Microsoft Academic Search

This paper investigates whether cannabis use affects physical and mental health. To do so, information on prime aged individuals living in Amsterdam in 1994 is used. Dutch data offer a clear advantage in estimating the health impacts of cannabis use because the legal status of cannabis in the Netherlands ensures that estimates are free from confounding with the physical and

Jenny Williams

2012-01-01

322

Efectos del cannabis sobre la salud mental en jóvenes consumidores  

Microsoft Academic Search

Summary This is the second part of a review of the damage to health associated with cannabis consumption among young people. The first part reviewed the available evidence about the adverse effects of cannabis on physical health. This second part deals with the available evidence about its effects on mental health. Cannabis has been considered a relatively harmless drug, and

L. Gutiérrez Rojas; J. De Irala; M. A. Martínez-González

2006-01-01

323

A community survey of adverse effects of cannabis use  

Microsoft Academic Search

This survey estimates the frequency of various adverse effects of the use of the drug cannabis. A sample of 1000 New Zealanders aged 18–35 years were asked to complete a self-administered questionnaire on cannabis use and associated problems. The questionnaire was derived from criteria for the identification of cannabis abuse which are analagous to criteria commonly used to diagnose alcoholism.

Huw Thomas

1996-01-01

324

Cannabis use is associated with schizotypy and attentional disinhibition  

E-print Network

Cannabis use is associated with schizotypy and attentional disinhibition Patrick D. Skosnika , Lea of the endogenous cannabinioid system, a re-examination of the cannabis-induced exacerbation hypothesis of SZ is warranted. The purpose of the present study was to assess whether current cannabis users exhibit personality

Park, Sohee

325

Assessment of different mouthwashes on cannabis oral fluid concentrations.  

PubMed

Since the implementation of mandatory drug testing in drivers' oral fluid, several solutions to avoid an onsite positive result can be found on drug users' forums, especially for marijuana, including the use of different mouthwashes. Recently, a product for personal hygiene, Kleaner, has been sold for this purpose. The aims of this study were to assess the effect of water, whole milk, and Kleaner mouthwashes on tetrahydrocannabinol (THC) oral fluid concentrations, and those observed in passive smokers subjected to extreme contamination conditions. The study was performed on four days. On day 0, study information was given to the participants. On days 1, 2, and 3, 11 chronic cannabis users smoked their usual daily dose, and oral fluid specimens were collected before smoking (t=-0.5h) and at t=0.25, 0.5, 1, 3, 6, 12, and 24 h post-smoking. On day 1, participants rinsed their mouth with water before each specimen collection. On day 2, 5 participants rinsed their mouth with Kleaner and 6 with whole milk. On day 3, a specimen was collected before and after rinsing the mouth with water. Statistically significant lower concentrations were observed comparing concentrations in oral fluid specimens collected before and after a water rinse. However, maximum THC concentrations at t=0.25h were >3-fold higher than the cut-off employed by the Spanish police (25 ng/mL) regardless of the use of any mouthwash. THC was also detected in the oral fluid of passive smokers subjected to extreme contamination conditions; however, concentrations were <25 ng/mL in all cases. Copyright © 2014 John Wiley & Sons, Ltd. PMID:24453092

de Castro, Ana; Lendoiro, Elena; Fernández-Vega, Hadriana; López-Rivadulla, Manuel; Steinmeyer, Stefan; Cruz, Angelines

2014-10-01

326

Approach-Bias Predicts Development of Cannabis Problem Severity in Heavy Cannabis Users: Results from a Prospective FMRI Study  

PubMed Central

A potentially powerful predictor for the course of drug (ab)use is the approach-bias, that is, the pre-reflective tendency to approach rather than avoid drug-related stimuli. Here we investigated the neural underpinnings of cannabis approach and avoidance tendencies. By elucidating the predictive power of neural approach-bias activations for future cannabis use and problem severity, we aimed at identifying new intervention targets. Using functional Magnetic Resonance Imaging (fMRI), neural approach-bias activations were measured with a Stimulus Response Compatibility task (SRC) and compared between 33 heavy cannabis users and 36 matched controls. In addition, associations were examined between approach-bias activations and cannabis use and problem severity at baseline and at six-month follow-up. Approach-bias activations did not differ between heavy cannabis users and controls. However, within the group of heavy cannabis users, a positive relation was observed between total lifetime cannabis use and approach-bias activations in various fronto-limbic areas. Moreover, approach-bias activations in the dorsolateral prefrontal cortex (DLPFC) and anterior cingulate cortex (ACC) independently predicted cannabis problem severity after six months over and beyond session-induced subjective measures of craving. Higher DLPFC/ACC activity during cannabis approach trials, but lower activity during cannabis avoidance trials were associated with decreases in cannabis problem severity. These findings suggest that cannabis users with deficient control over cannabis action tendencies are more likely to develop cannabis related problems. Moreover, the balance between cannabis approach and avoidance responses in the DLPFC and ACC may help identify individuals at-risk for cannabis use disorders and may be new targets for prevention and treatment. PMID:22957019

Cousijn, Janna; Goudriaan, Anna E.; Ridderinkhof, K. Richard; van den Brink, Wim; Veltman, Dick J.; Wiers, Reinout W.

2012-01-01

327

The occurrence of cannabis use disorders and other cannabis-related problems among first-year college students  

Microsoft Academic Search

This study reports the prevalence of cannabis use disorders (CUD) and other cannabis-related problems in a large cohort (n=1253) of first-year college students, 17 to 20 years old, at one large public university in the mid-Atlantic region of the U.S. Interviewers assessed past-year cannabis use, other drug use, and cannabis-related problems (including DSM-IV criteria for CUD). The prevalence of CUD was

Kimberly M. Caldeira; Amelia M. Arria; Kevin E. O'Grady; Kathryn B. Vincent; Eric D. Wish

2008-01-01

328

The current status of medical marijuana in the United States.  

PubMed

Medical marijuana is currently a controversial issue in medicine. There are strong pro and con opinions but relatively little scientific data on which to base medical decisions. The unfortunate scheduling of marijuana in class I has limited research and only serves to fuel the controversy. This article will review the history of laws to regulate drugs in the United States in the 20th century to provide context for the current status of medical marijuana. It will include the rationale for opposing medical marijuana laws and the problem of the Schedule I inclusion of marijuana as well as other drugs. It will examine the problems associated with smoking raw marijuana and review other routes of administration. Finally, it examines the inadvisability of medicine's promotion of smoked marijuana. PMID:24765557

McKenna, Gerald J

2014-04-01

329

The Current Status of Medical Marijuana in the United States  

PubMed Central

Medical marijuana is currently a controversial issue in medicine. There are strong pro and con opinions but relatively little scientific data on which to base medical decisions. The unfortunate scheduling of marijuana in class I has limited research and only serves to fuel the controversy. This article will review the history of laws to regulate drugs in the United States in the 20th century to provide context for the current status of medical marijuana. It will include the rationale for opposing medical marijuana laws and the problem of the Schedule I inclusion of marijuana as well as other drugs. It will examine the problems associated with smoking raw marijuana and review other routes of administration. Finally, it examines the inadvisability of medicine's promotion of smoked marijuana. PMID:24765557

2014-01-01

330

[Medical cannabis: the opportunity versus the temptation].  

PubMed

The cannabis plant has been known to humanity for centuries as a remedy for pain, diarrhea, and inflammation. Current research has shown cannabis to be a useful remedy for many diseases, including multiple sclerosis, dystonia, and chronic pain. Cannabinoids are used to improve food intake in anorexia of AIDS patients and to prevent vomiting due to cancer chemotherapy. In inflammatory conditions cannabinoids improve pain in rheumatoid arthritis and pain and diarrhea in Crohn's disease. Cannabinoids reduce the size of brain infarct and cardiac reperfusion injury. However, cannabinoid treatment is not free of side effects including euphoria, psychosis, anxiety, paranoia, dependence and abuse. Since the cannabinoid system is involved in many physiological and pathological processes, the therapeutic potential is great. We must not be blind to the opportunity offered to us by medical cannabis just because it is an illicit drug, nor should we be temped by the quick response of patients to the central effect of cannabis. More research is warranted to explore the full potential of cannabis as medicine. PMID:22352284

Naftali, Timna

2011-12-01

331

Weed or Wheel! fMRI, Behavioural, and Toxicological Investigations of How Cannabis Smoking Affects Skills Necessary for Driving  

PubMed Central

Marijuana is the most widely used illicit drug, however its effects on cognitive functions underling safe driving remain mostly unexplored. Our goal was to evaluate the impact of cannabis on the driving ability of occasional smokers, by investigating changes in the brain network involved in a tracking task. The subject characteristics, the percentage of ?9-Tetrahydrocannabinol in the joint, and the inhaled dose were in accordance with real-life conditions. Thirty-one male volunteers were enrolled in this study that includes clinical and toxicological aspects together with functional magnetic resonance imaging of the brain and measurements of psychomotor skills. The fMRI paradigm was based on a visuo-motor tracking task, alternating active tracking blocks with passive tracking viewing and rest condition. We show that cannabis smoking, even at low ?9-Tetrahydrocannabinol blood concentrations, decreases psychomotor skills and alters the activity of the brain networks involved in cognition. The relative decrease of Blood Oxygen Level Dependent response (BOLD) after cannabis smoking in the anterior insula, dorsomedial thalamus, and striatum compared to placebo smoking suggests an alteration of the network involved in saliency detection. In addition, the decrease of BOLD response in the right superior parietal cortex and in the dorsolateral prefrontal cortex indicates the involvement of the Control Executive network known to operate once the saliencies are identified. Furthermore, cannabis increases activity in the rostral anterior cingulate cortex and ventromedial prefrontal cortices, suggesting an increase in self-oriented mental activity. Subjects are more attracted by intrapersonal stimuli (“self”) and fail to attend to task performance, leading to an insufficient allocation of task-oriented resources and to sub-optimal performance. These effects correlate with the subjective feeling of confusion rather than with the blood level of ?9-Tetrahydrocannabinol. These findings bolster the zero-tolerance policy adopted in several countries that prohibits the presence of any amount of drugs in blood while driving. PMID:23300977

Thomas, Aurelien; Mall, Jean-Frederic; Chtioui, Haithem; Appenzeller, Monique; Annoni, Jean-Marie; Favrat, Bernard

2013-01-01

332

Weed or wheel! FMRI, behavioural, and toxicological investigations of how cannabis smoking affects skills necessary for driving.  

PubMed

Marijuana is the most widely used illicit drug, however its effects on cognitive functions underlying safe driving remain mostly unexplored. Our goal was to evaluate the impact of cannabis on the driving ability of occasional smokers, by investigating changes in the brain network involved in a tracking task. The subject characteristics, the percentage of ?(9)-Tetrahydrocannabinol in the joint, and the inhaled dose were in accordance with real-life conditions. Thirty-one male volunteers were enrolled in this study that includes clinical and toxicological aspects together with functional magnetic resonance imaging of the brain and measurements of psychomotor skills. The fMRI paradigm was based on a visuo-motor tracking task, alternating active tracking blocks with passive tracking viewing and rest condition. We show that cannabis smoking, even at low ?(9)-Tetrahydrocannabinol blood concentrations, decreases psychomotor skills and alters the activity of the brain networks involved in cognition. The relative decrease of Blood Oxygen Level Dependent response (BOLD) after cannabis smoking in the anterior insula, dorsomedial thalamus, and striatum compared to placebo smoking suggests an alteration of the network involved in saliency detection. In addition, the decrease of BOLD response in the right superior parietal cortex and in the dorsolateral prefrontal cortex indicates the involvement of the Control Executive network known to operate once the saliencies are identified. Furthermore, cannabis increases activity in the rostral anterior cingulate cortex and ventromedial prefrontal cortices, suggesting an increase in self-oriented mental activity. Subjects are more attracted by intrapersonal stimuli ("self") and fail to attend to task performance, leading to an insufficient allocation of task-oriented resources and to sub-optimal performance. These effects correlate with the subjective feeling of confusion rather than with the blood level of ?(9)-Tetrahydrocannabinol. These findings bolster the zero-tolerance policy adopted in several countries that prohibits the presence of any amount of drugs in blood while driving. PMID:23300977

Battistella, Giovanni; Fornari, Eleonora; Thomas, Aurélien; Mall, Jean-Frédéric; Chtioui, Haithem; Appenzeller, Monique; Annoni, Jean-Marie; Favrat, Bernard; Maeder, Philippe; Giroud, Christian

2013-01-01

333

Analysis of cannabis seizures in NSW, Australia: cannabis potency and cannabinoid profile.  

PubMed

Recent analysis of the cannabinoid content of cannabis plants suggests a shift towards use of high potency plant material with high levels of ?(9)-tetrahydrocannabinol (THC) and low levels of other phytocannabinoids, particularly cannabidiol (CBD). Use of this type of cannabis is thought by some to predispose to greater adverse outcomes on mental health and fewer therapeutic benefits. Australia has one of the highest per capita rates of cannabis use in the world yet there has been no previous systematic analysis of the cannabis being used. In the present study we examined the cannabinoid content of 206 cannabis samples that had been confiscated by police from recreational users holding 15 g of cannabis or less, under the New South Wales "Cannabis Cautioning" scheme. A further 26 "Known Provenance" samples were analysed that had been seized by police from larger indoor or outdoor cultivation sites rather than from street level users. An HPLC method was used to determine the content of 9 cannabinoids: THC, CBD, cannabigerol (CBG), and their plant-based carboxylic acid precursors THC-A, CBD-A and CBG-A, as well as cannabichromene (CBC), cannabinol (CBN) and tetrahydrocannabivarin (THC-V). The "Cannabis Cautioning" samples showed high mean THC content (THC+THC-A?=?14.88%) and low mean CBD content (CBD+CBD-A?=?0.14%). A modest level of CBG was detected (CBG+CBG-A?=?1.18%) and very low levels of CBC, CBN and THC-V (<0.1%). "Known Provenance" samples showed no significant differences in THC content between those seized from indoor versus outdoor cultivation sites. The present analysis echoes trends reported in other countries towards the use of high potency cannabis with very low CBD content. The implications for public health outcomes and harm reduction strategies are discussed. PMID:23894589

Swift, Wendy; Wong, Alex; Li, Kong M; Arnold, Jonathon C; McGregor, Iain S

2013-01-01

334

Analysis of Cannabis Seizures in NSW, Australia: Cannabis Potency and Cannabinoid Profile  

PubMed Central

Recent analysis of the cannabinoid content of cannabis plants suggests a shift towards use of high potency plant material with high levels of ?9-tetrahydrocannabinol (THC) and low levels of other phytocannabinoids, particularly cannabidiol (CBD). Use of this type of cannabis is thought by some to predispose to greater adverse outcomes on mental health and fewer therapeutic benefits. Australia has one of the highest per capita rates of cannabis use in the world yet there has been no previous systematic analysis of the cannabis being used. In the present study we examined the cannabinoid content of 206 cannabis samples that had been confiscated by police from recreational users holding 15 g of cannabis or less, under the New South Wales “Cannabis Cautioning” scheme. A further 26 “Known Provenance” samples were analysed that had been seized by police from larger indoor or outdoor cultivation sites rather than from street level users. An HPLC method was used to determine the content of 9 cannabinoids: THC, CBD, cannabigerol (CBG), and their plant-based carboxylic acid precursors THC-A, CBD-A and CBG-A, as well as cannabichromene (CBC), cannabinol (CBN) and tetrahydrocannabivarin (THC-V). The “Cannabis Cautioning” samples showed high mean THC content (THC+THC-A?=?14.88%) and low mean CBD content (CBD+CBD-A?=?0.14%). A modest level of CBG was detected (CBG+CBG-A?=?1.18%) and very low levels of CBC, CBN and THC-V (<0.1%). “Known Provenance” samples showed no significant differences in THC content between those seized from indoor versus outdoor cultivation sites. The present analysis echoes trends reported in other countries towards the use of high potency cannabis with very low CBD content. The implications for public health outcomes and harm reduction strategies are discussed. PMID:23894589

Li, Kong M.; Arnold, Jonathon C.; McGregor, Iain S.

2013-01-01

335

An approach to the medical marijuana controversy  

Microsoft Academic Search

The use of smoked marijuana as a therapeutic agent is presently a matter of considerable debate in the United States. Many people suffering from a variety of disorders maintain that it is necessary for their adequate treatment. Yet, the evidence to support claims is insufficient for FDA approval. An interim solution is proposed which would allow patients referred by their

L. E Hollister

2000-01-01

336

Marijuana use motives: concurrent relations to frequency of past 30-day use and anxiety sensitivity among young adult marijuana smokers.  

PubMed

The present investigation examined two theoretically relevant aspects of marijuana motives using the Marijuana Motives Measure (MMM) [Simons, J., Correia, C. J., Carey, K. B., & Borsari, B. E. (1998). Validating a five-factor marijuana motives measure: Relations with use, problems, and alcohol motives. Journal of Counseling Psychology 45, 265-273] among 141 (78 female) young adults (M(age)=20.17, S.D.=3.34). The first objective was to evaluate the incremental validity of marijuana motives in relation to frequency of past 30-day use after controlling for the theoretically relevant factors of the number of years using marijuana (lifetime), current levels of alcohol, as well as tobacco smoking use. As expected, coping, enhancement, social, and expansion motives each were uniquely and significantly associated with past 30-day marijuana use over and above the covariates; conformity motives were not a significant predictor. A second aim was to explore whether coping, but no other marijuana motive, was related to the emotional vulnerability individual difference factor of anxiety sensitivity (fear of anxiety). As hypothesized, after controlling for number of years using marijuana (lifetime), past 30-day marijuana use, current levels of alcohol consumption, and cigarettes smoked per day, anxiety sensitivity was incrementally and uniquely related to coping motives for marijuana use, but not other motives. These results are discussed in relation to the clinical implications of better understanding the role of motivation for marijuana use among emotionally vulnerable young adults. PMID:16647822

Bonn-Miller, Marcel O; Zvolensky, Michael J; Bernstein, Amit

2007-01-01

337

Frequencies of hprt mutant lymphocytes in marijuana-smoking mothers and their newborns  

Microsoft Academic Search

Reports of increases in the prevalence of marijuana smoking, especially among young people, have led to concerns about possible genotoxic effects from marijuana use due to exposure to the mutagenic and carcinogenic agents present in marijuana smoke. Prior studies of the adverse healt consequences of marijuana smoking, using disease outcomes, have sometimes been confounded by the fact that most marijuana

Marinel M. Ammenheuser; Abbey B. Berenson; Adriana E. Babiak; Chantele R. Singleton; Elbert B. Whorton

1998-01-01

338

Effects of acute smoked marijuana on complex cognitive performance.  

PubMed

Although the ability to perform complex cognitive operations is assumed to be impaired following acute marijuana smoking, complex cognitive performance after acute marijuana use has not been adequately assessed under experimental conditions. In the present study, we used a within-participant double-blind design to evaluate the effects acute marijuana smoking on complex cognitive performance in experienced marijuana smokers. Eighteen healthy research volunteers (8 females, 10 males), averaging 24 marijuana cigarettes per week, completed this three-session outpatient study; sessions were separated by at least 72-hrs. During sessions, participants completed baseline computerized cognitive tasks, smoked a single marijuana cigarette (0%, 1.8%, or 3.9% Delta(9)-THC w/w), and completed additional cognitive tasks. Blood pressure, heart rate, and subjective effects were also assessed throughout sessions. Marijuana cigarettes were administered in a double-blind fashion and the sequence of Delta(9)-THC concentration order was balanced across participants. Although marijuana significantly increased the number of premature responses and the time participants required to complete several tasks, it had no effect on accuracy on measures of cognitive flexibility, mental calculation, and reasoning. Additionally, heart rate and several subjective-effect ratings (e.g., "Good Drug Effect," "High," "Mellow") were significantly increased in a Delta(9)-THC concentration-dependent manner. These data demonstrate that acute marijuana smoking produced minimal effects on complex cognitive task performance in experienced marijuana users. PMID:11682259

Hart, C L; van Gorp, W; Haney, M; Foltin, R W; Fischman, M W

2001-11-01

339

Two cases of "cannabis acute psychosis" following the administration of oral cannabis  

PubMed Central

Background Cannabis is the most commonly used illegal drug and its therapeutic aspects have a growing interest. Short-term psychotic reactions have been described but not clearly with synthetic oral THC, especially in occasional users. Case presentations We report two cases of healthy subjects who were occasional but regular cannabis users without psychiatric history who developed transient psychotic symptoms (depersonalization, paranoid feelings and derealisation) following oral administration of cannabis. In contrast to most other case reports where circumstances and blood concentrations are unknown, the two cases reported here happened under experimental conditions with all subjects negative for cannabis, opiates, amphetamines, cocaine, benzodiazepines and alcohol, and therefore the ingested dose, the time-events of effects on behavior and performance as well as the cannabinoid blood levels were documented. Conclusion While the oral route of administration achieves only limited blood concentrations, significant psychotic reactions may occur. PMID:15804348

Favrat, Bernard; Menetrey, Annick; Augsburger, Marc; Rothuizen, Laura E; Appenzeller, Monique; Buclin, Thierry; Pin, Marie; Mangin, Patrice; Giroud, Christian

2005-01-01

340

Mechanisms Underlying the Link between Cannabis Use and Prospective Memory  

PubMed Central

While the effects of cannabis use on retrospective memory have been extensively examined, only a limited number of studies have focused on the links between cannabis use and prospective memory. We conducted two studies to examine the links between cannabis use and both time-based and event-based prospective memory as well as potential mechanisms underlying these links. For the first study, 805 students completed an online survey designed to assess cannabis consumption, problems with cannabis use indicative of a disorder, and frequency of experiencing prospective memory failures. The results showed small to moderate sized correlations between cannabis consumption, problems with cannabis use, and prospective memory. However, a series of mediation analyses revealed that correlations between problems with cannabis use and prospective memory were driven by self-reported problems with retrospective memory. For the second study, 48 non-users (who had never used cannabis), 48 experimenters (who had used cannabis five or fewer times in their lives), and 48 chronic users (who had used cannabis at least three times a week for one year) were administered three objective prospective memory tests and three self-report measures of prospective memory. The results revealed no objective deficits in prospective memory associated with chronic cannabis use. In contrast, chronic cannabis users reported experiencing more internally-cued prospective memory failures. Subsequent analyses revealed that this effect was driven by self-reported problems with retrospective memory as well as by use of alcohol and other drugs. Although our samples were not fully characterized with respect to variables such as neurological disorders and family history of substance use disorders, leaving open the possibility that these variables may play a role in the detected relationships, the present findings indicate that cannabis use has a modest effect on self-reported problems with prospective memory, with a primary problem with retrospective memory appearing to underlie this relationship. PMID:22606293

Cuttler, Carrie; McLaughlin, Ryan J.; Graf, Peter

2012-01-01

341

Cannabis in Multiple Sclerosis: Women's Health Concerns  

Microsoft Academic Search

Women's health has received greater attention with the recognition of significant differences in disease expression and drug action in men and women. Multiple sclerosis is a neurological disorder with important gender differences. MS patients have employed cannabis to treat a number of symptoms associated with the disease including spasticity, pain, tremor, fatigue, and autonomic dysfunction. The scientific literature includes supportive

Denis J. Petro

2002-01-01

342

The Impact of Cannabis Use on Health  

Microsoft Academic Search

Summary  Chronic daily cannabis use has been shown to have long term harmful health effects, which in turn is expected to reduce labour market productivity. The evidence is less clear on the health impact of less frequent consumption, which is the more typical mode of use, and previous empirical studies fail to find robust evidence of an adverse impact of these

Jenny Williams; Christopher L. Skeels

2006-01-01

343

32 CFR 700.1138 - Responsibilities concerning marijuana, narcotics, and other controlled substances.  

... false Responsibilities concerning marijuana, narcotics, and other controlled substances...1138 Responsibilities concerning marijuana, narcotics, and other controlled substances...and eliminate the unauthorized use of marijuana, narcotics and other controlled...

2014-07-01

344

Some physical characteristics of NIDA marijuana cigarettes.  

PubMed

Marijuana cigarettes of three different potencies (0.0%, 1.4% and 2.7% delta-9-tetrahydrocannabinol (THC) content) provided by the National Institute on Drug Abuse (NIDA) were compared on a variety of characteristics, including physical appearance, weight, burn rate, and deliveries of total particulate matter and carbon monoxide. Significant differences between the different potency cigarettes were obtained on most measures. These differences could be relevant to the design and interpretation of pharmacologic/toxicologic and behavioral studies conducted with these cigarettes. The possible basis for these observed differences, methods for minimizing some of them, and other potential problems related to the use of NIDA marijuana cigarettes are discussed. PMID:2718825

Chait, L D; Pierri, J

1989-01-01

345

The Influence of Early and Frequent Use of Marijuana on the Risk of Desistance and of Progression to Marijuana-Related Harm  

Microsoft Academic Search

Background. A significant minority of lifetime marijuana users will eventually receive a diagnosis of abuse or dependence. Yet little is known regarding the effect of age at onset and frequency of lifetime marijuana use on desistance from use and on progression to marijuana disorders.Methods. To address this issue, data were obtained from a community sample of 2,729 lifetime marijuana users

David J. DeWit; Jennifer Hance; David R. Offord; Alan Ogborne

2000-01-01

346

Exploring the Impact of Medical Marijuana Laws on the Validity of Self-Reported Marijuana Use Among Juvenile Arrestees Over Time  

Microsoft Academic Search

Past studies have found that underreporting of marijuana use is particularly high. The present study extends previous research that examined the temporal validity of self-reported marijuana use among juvenile arrestees. Furthermore, the present study explores whether the passage of medical marijuana laws in some states have affected the validity of self-reported marijuana use among juvenile arrestees. Using existing juvenile offender

Riane N. Miller; Joseph B. Kuhns

2012-01-01

347

Physician Attitudes Regarding the Prescription of Medical Marijuana  

Microsoft Academic Search

Surveys of physicians' attitudes regarding the therapeutic value of marijuana are rare. Drawing on a national sample of family physicians, general internists, obstetrician-gynecologists, psychiatrists, and addiction specialists, 960 (adjusted response rate 66%) offered opinions about the legal prescription of “marijuana as medical therapy.” Thirty-six percent believed prescribed marijuana should be legal and 26% were neutral to the proposition. Non-moralistic attitudes

Anthony Charuvastra; Peter D. Friedmann; Michael D. Stein

2005-01-01

348

Medical Marijuana: A Survey of Teenagers and Their Parents  

Microsoft Academic Search

Parents and their teenage children were questioned about medical marijuana and whether they believed that passage of medical marijuana laws in their states would increase teenage use of marijuana for non-medical purposes. A 24-question written survey was distributed separately to teenager\\/parent pairs who visited 1 of 2 suburban general pediatric offices located in Vienna, Virginia or Mason, Ohio. Completed surveys

Richard H. Schwartz; Meghan N. Cooper; Marife Oria; Michael J. Sheridan

2003-01-01

349

Genetic predisposition to schizophrenia associated with increased use of cannabis.  

PubMed

Cannabis is the most commonly used illicit drug worldwide. With debate surrounding the legalization and control of use, investigating its health risks has become a pressing area of research. One established association is that between cannabis use and schizophrenia, a debilitating psychiatric disorder affecting ~1% of the population over their lifetime. Although considerable evidence implicates cannabis use as a component cause of schizophrenia, it remains unclear whether this is entirely due to cannabis directly raising risk of psychosis, or whether the same genes that increases psychosis risk may also increase risk of cannabis use. In a sample of 2082 healthy individuals, we show an association between an individual's burden of schizophrenia risk alleles and use of cannabis. This was significant both for comparing those who have ever versus never used cannabis (P=2.6 × 10(-)(4)), and for quantity of use within users (P=3.0 × 10(-3)). Although directly predicting only a small amount of the variance in cannabis use, these findings suggest that part of the association between schizophrenia and cannabis is due to a shared genetic aetiology. This form of gene-environment correlation is an important consideration when calculating the impact of environmental risk factors, including cannabis use. PMID:24957864

Power, R A; Verweij, K J H; Zuhair, M; Montgomery, G W; Henders, A K; Heath, A C; Madden, P A F; Medland, S E; Wray, N R; Martin, N G

2014-11-01

350

Decreased respiratory symptoms in cannabis users who vaporize  

PubMed Central

Cannabis smoking can create respiratory problems. Vaporizers heat cannabis to release active cannabinoids, but remain cool enough to avoid the smoke and toxins associated with combustion. Vaporized cannabis should create fewer respiratory symptoms than smoked cannabis. We examined self-reported respiratory symptoms in participants who ranged in cigarette and cannabis use. Data from a large Internet sample revealed that the use of a vaporizer predicted fewer respiratory symptoms even when age, sex, cigarette smoking, and amount of cannabis used were taken into account. Age, sex, cigarettes, and amount of cannabis also had significant effects. The number of cigarettes smoked and amount of cannabis used interacted to create worse respiratory problems. A significant interaction revealed that the impact of a vaporizer was larger as the amount of cannabis used increased. These data suggest that the safety of cannabis can increase with the use of a vaporizer. Regular users of joints, blunts, pipes, and water pipes might decrease respiratory symptoms by switching to a vaporizer PMID:17437626

Earleywine, Mitch; Barnwell, Sara Smucker

2007-01-01

351

Comparison of bulk and compound-specific ?13C isotope ratio analyses for the discrimination between cannabis samples.  

PubMed

Five marijuana samples were compared using bulk isotope analysis compound-specific isotope ratio analysis of the extracted cannabinoids. Owing to the age of our cannabis samples, four of the five samples were compared using the isotope ratios of cannabinol (CBN), a stable degradation product of ?(9)-tetrahydrocannabinol (THC). Bulk ?(13)C isotope analysis discriminated between all five samples at the 95% confidence level. Compound-specific ?(13)C isotope analysis could not distinguish between one pair of the five samples at the 95% confidence level. All the measured cannabinoids showed significant depletion in (13)C relative to bulk isotope values; the isotope ratios for THC, CBN, and cannabidiol were on average 1.6‰, 1.7‰, and 2.2‰ more negative than the bulk values, respectively. A more detailed investigation needs to be conducted to assess the degree fractionation between the different cannabinoids, especially after aging. PMID:22292792

Muccio, Zeland; Wöckel, Claudia; An, Yan; Jackson, Glen P

2012-05-01

352

Dimensions and Severity of Marijuana Consequences: Development and Validation of the Marijuana Consequences Questionnaire (MACQ)  

PubMed Central

The Marijuana Consequences Questionnaire (MACQ) is a 50-item self-report measure modeled after the Young Adult Alcohol Consequences Questionnaire (YAACQ). College students (n = 315) completed questionnaires online. A confirmatory factor analysis supported the hypothesized 8-factor structure. The results indicate good convergent and discriminant validity of the MACQ. A brief, unidimensional, 21-item version (B-MACQ) was developed by a Rasch model. Comparison of item severity estimates of the B-MACQ items and the corresponding items from the YAACQ indicate that the severity of alcohol- and marijuana- problems is defined by a relatively unique pattern of consequences. The MACQ and B-MACQ provide promising new alternatives to assessing marijuana-related problems. PMID:22305645

Simons, Jeffrey S.; Dvorak, Robert D.; Merrill, Jennifer E.; Read, Jennifer P.

2012-01-01

353

Failure to Sustain Prepulse Inhibition in Adolescent Marijuana Users  

PubMed Central

Background Marijuana use is typically initiated during adolescence, which is a critical period for neural development. Studies have reported reductions in prepulse inhibition (PPI) among adults who use marijuana chronically, although no human studies have been conducted during the critical adolescent period. Methods This study tested PPI of acoustic startle among adolescents who were either frequent marijuana Users or naïve to the drug (Controls). Adolescents were tested using two intensities of prepulses (70 and 85 dB) combined with a 105 dB startle stimulus, delivered across two testing blocks. Results There was a significant interaction of group by block for PPI; marijuana Users experienced a greater decline in the PPI across the testing session than Controls. The change in PPI of response magnitude for Users was predicted by change in urine THC/creatinine after atleast 18 hours of abstinence, the number of joints used during the previous week before testing, as well as self-reported DSM-IV symptoms of marijuana tolerance, and time spent using marijuana rather than participating in other activities. Conclusions These outcomes suggest that adolescents who are frequent marijuana users have problems maintaining of prepulse inhibition, possibly due to lower quality of information processing or sustained attention, both of may contribute to maintaining continued marijuana use as well as attrition from marijuana treatment. PMID:21196088

Mathias, Charles W.; Blumenthal, Terry D.; Dawes, Michael A.; Liguori, Anthony; Richard, Dawn M.; Bray, Bethany; Tong, Weiqun; Dougherty, Donald M.

2011-01-01

354

Physician attitudes regarding the prescription of medical marijuana.  

PubMed

Surveys of physicians' attitudes regarding the therapeutic value of marijuana are rare. Drawing on a national sample of family physicians, general internists, obstetrician-gynecologists, psychiatrists, and addiction specialists, 960 (adjusted response rate 66%) offered opinions about the legal prescription of marijuana as medical therapy. Thirty-six percent believed prescribed marijuana should be legal and 26% were neutral to the proposition. Non-moralistic attitudes toward substance use were significantly associated with support for physician prescription, as was internal medicine and obstetrics-gynecology specialization. Physicians are, in general, less supportive than the general American public regarding the use of medical marijuana. PMID:16186085

Charuvastra, Anthony; Friedmann, Peter D; Stein, Michael D

2005-01-01

355

Marijuana use motives: Concurrent relations to frequency of past 30-day use and anxiety sensitivity among young adult marijuana smokers  

Microsoft Academic Search

The present investigation examined two theoretically relevant aspects of marijuana motives using the Marijuana Motives Measure (MMM) [Simons, J., Correia, C. J., Carey, K. B., & Borsari, B. E. (1998). Validating a five-factor marijuana motives measure: Relations with use, problems, and alcohol motives. Journal of Counseling Psychology 45, 265–273] among 141 (78 female) young adults (Mage=20.17, S.D.=3.34). The first objective

Marcel O. Bonn-Miller; Michael J. Zvolensky; Amit Bernstein

2007-01-01

356

Poor School Satisfaction and Number of Cannabis Using Peers within School Classes as Individual Risk Factors for Cannabis Use among Adolescents  

ERIC Educational Resources Information Center

There is little information available on the topic of poor school satisfaction as a risk factor for cannabis use among adolescents. We examined if there was an association between poor school satisfaction, school class cannabis use and individual cannabis use. Further, we investigated if many cannabis users within the school class statistically…

Hoff, Dominic A.; Andersen, Anette; Holstein, Bjorn E.

2010-01-01

357

Cross-national differences in clinically significant cannabis problems: epidemiologic evidence from 'cannabis-only' smokers in the United States, Mexico, and Colombia  

Microsoft Academic Search

BACKGROUND: Epidemiological studies show wide variability in the occurrence of cannabis smoking and related disorders across countries. This study aims to estimate cross-national variation in cannabis users' experience of clinically significant cannabis-related problems in three countries of the Americas, with a focus on cannabis users who may have tried alcohol or tobacco, but who have not used cocaine, heroin, LSD,

Fabian Fiestas; Mirjana Radovanovic; Silvia S Martins; Maria E Medina-Mora; Jose Posada-Villa; James C Anthony

2010-01-01

358

Performance of young adult cannabis users on neurocognitive measures of impulsive behavior and their relationship to symptoms of cannabis use disorders  

Microsoft Academic Search

Recent studies suggest that abstinent cannabis users show deficits on neurocognitive laboratory tasks of impulsive behavior. But results are mixed, and less is known on the performance of non-treatment-seeking, young adult cannabis users. Importantly, relationships between performance on measures of impulsive behavior and symptoms of cannabis addiction remain relatively unexplored. We compared young adult current cannabis users (CU, n?=?65) and

Raul Gonzalez; Randi Melissa Schuster; Robin J. Mermelstein; Jasmin Vassileva; Eileen M. Martin; Kathleen R. Diviak

2012-01-01

359

A Genomewide Association Study of DSM-IV Cannabis Dependence  

PubMed Central

Despite twin studies showing that 50–70% of variation in DSM-IV cannabis dependence is attributable to heritable influences, little is known of specific genotypes that influence vulnerability to cannabis dependence. We conducted a genomewide association study of DSM-IV cannabis dependence. Association analyses of 708 DSM-IV cannabis dependent cases with 2,346 cannabis exposed nondependent controls was conducted using logistic regression in PLINK. None of the 948,142 SNPs met genomewide significance (p < E?8). The lowest p-values were obtained for polymorphisms on chromosome 17 (rs1019238 and rs1431318, p-values at E?7) in the ANKFN1 gene. While replication is required, this study represents an important first step towards clarifying the biological underpinnings of cannabis dependence. PMID:21668797

Agrawal, Arpana; Lynskey, Michael T.; Hinrichs, Anthony; Grucza, Richard; Saccone, Scott F.; Krueger, Robert; Neuman, Rosalind; Howells, William; Fisher, Sherri; Fox, Louis; Cloninger, Robert; Dick, Danielle M.; Doheny, Kimberly F.; Edenberg, Howard J.; Goate, Alison M.; Hesselbrock, Victor; Johnson, Eric; Kramer, John; Kuperman, Samuel; Nurnberger, John I; Pugh, Elizabeth; Schuckit, Marc; Tischfield, Jay; Rice, John P.; Bucholz, Kathleen K.; Bierut, Laura J.

2010-01-01

360

Cannabis use in HIV for pain and other medical symptoms.  

PubMed

Despite the major benefits of antiretroviral therapy on survival during HIV infection, there is an increasing need to manage symptoms and side effects during long-term drug therapy. Cannabis has been reported anecdotally as being beneficial for a number of common symptoms and complications in HIV infections, for example, poor appetite and neuropathy. This study aimed to investigate symptom management with cannabis. Following Ethics Committee approval, HIV-positive individuals attending a large clinic were recruited into an anonymous cross-sectional questionnaire study. Up to one-third (27%, 143/523) reported using cannabis for treating symptoms. Patients reported improved appetite (97%), muscle pain (94%), nausea (93%), anxiety (93%), nerve pain (90%), depression (86%), and paresthesia (85%). Many cannabis users (47%) reported associated memory deterioration. Symptom control using cannabis is widespread in HIV outpatients. A large number of patients reported that cannabis improved symptom control. PMID:15857739

Woolridge, Emily; Barton, Simon; Samuel, Jonathon; Osorio, Jess; Dougherty, Andrew; Holdcroft, Anita

2005-04-01

361

The effects of cannabis use on physical and mental health.  

PubMed

This paper investigates whether cannabis use affects physical and mental health. To do so, information on prime aged individuals living in Amsterdam in 1994 is used. Dutch data offer a clear advantage in estimating the health impacts of cannabis use because the legal status of cannabis in the Netherlands ensures that estimates are free from confounding with the physical and psychological effects of engaging in a criminal activity. Accounting for selection into cannabis use and shared frailties in mental and physical health, the results suggest that cannabis use reduces the mental wellbeing of men and women and the physical wellbeing of men. Although statistically significant, the magnitude of the effect of using cannabis on mental and physical health is found to be small. PMID:22664772

van Ours, Jan C; Williams, Jenny

2012-07-01

362

Individual and Additive Effects of the CNR1 and FAAH Genes on Brain Response to Marijuana Cues  

PubMed Central

As previous work has highlighted the significance of the cannabinoid receptor 1 (CNR1) and fatty acid amide hydrolase (FAAH) genes with respect to cannabis dependence (CD), this study sought to characterize the neural mechanisms that underlie these genetic effects. To this end, we collected DNA samples and fMRI data using a cue-elicited craving paradigm in thirty-seven 3-day-abstinent regular marijuana users. The participants were grouped according to their genotype on two single-nucleotide polymorphisms (SNPs) earlier associated with CD phenotypes: rs2023239 in CNR1 and rs324420 in FAAH. Between-group comparisons showed that carriers of the CNR1 rs2023239 G allele had significantly greater activity in reward-related areas of the brain, such as the orbitofrontal cortex (OFC), inferior frontal gyrus (IFG), and anterior cingulate gyrus (ACG), during exposure to marijuana cues, as compared with those with the A/A genotype for this SNP. The FAAH group contrasts showed that FAAH rs324420 C homozygotes also had greater activation in widespread areas within the reward circuit, specifically in the OFC, ACG, and nucleus accumbens (NAc), as compared with the FAAH A-allele carriers. Moreover, there was a positive correlation between neural response in OFC and NAc and the total number of risk alleles (cluster-corrected p<0.05). These findings are in accord with earlier reported associations between CNR1 and FAAH and CD intermediate phenotypes, and suggest that the underlying mechanism of these genetic effects may be enhanced neural response in reward areas of the brain in carriers of the CNR1 G allele and FAAH C/C genotype in response to marijuana cues. PMID:20010552

Filbey, Francesca M; Schacht, Joseph P; Myers, Ursula S; Chavez, Robert S; Hutchison, Kent E

2010-01-01

363

The effect of cannabis use on memory function: an update.  

PubMed

Investigating the effects of cannabis use on memory function appears challenging. While early observational investigations aimed to elucidate the longer-term effects of cannabis use on memory function in humans, findings remained equivocal and pointed to a pattern of interacting factors impacting on the relationship between cannabis use and memory function, rather than a simple direct effect of cannabis. Only recently, a clearer picture of the chronic and acute effects of cannabis use on memory function has emerged once studies have controlled for potential confounding factors and started to investigate the acute effects of delta-9-tetrahydrocannabinol (?9-THC) and cannabidiol (CBD), the main ingredients in the extract of the cannabis plant in pharmacological challenge experiments. Relatively consistent findings have been reported regarding the acute impairments induced by a single dose of ?9-THC on verbal and working memory. It is unclear whether they may persist beyond the intoxication state. In the long-term, these impairments seem particularly likely to manifest and may also persist following abstinence if regular and heavy use of cannabis strains high in ?9-THC is started at an early age. Although still at an early stage, studies that employed advanced neuroimaging techniques have started to model the neural underpinnings of the effects of cannabis use and implicate a network of functional and morphological alterations that may moderate the effects of cannabis on memory function. Future experimental and epidemiological studies that take into consideration individual differences, particularly previous cannabis history and demographic characteristics, but also the precise mixture of the ingredients of the consumed cannabis are necessary to clarify the magnitude and the mechanisms by which cannabis-induced memory impairments occur and to elucidate underlying neurobiological mechanisms. PMID:24648785

Schoeler, Tabea; Bhattacharyya, Sagnik

2013-01-01

364

The effect of cannabis use on memory function: an update  

PubMed Central

Investigating the effects of cannabis use on memory function appears challenging. While early observational investigations aimed to elucidate the longer-term effects of cannabis use on memory function in humans, findings remained equivocal and pointed to a pattern of interacting factors impacting on the relationship between cannabis use and memory function, rather than a simple direct effect of cannabis. Only recently, a clearer picture of the chronic and acute effects of cannabis use on memory function has emerged once studies have controlled for potential confounding factors and started to investigate the acute effects of delta-9-tetrahydrocannabinol (?9-THC) and cannabidiol (CBD), the main ingredients in the extract of the cannabis plant in pharmacological challenge experiments. Relatively consistent findings have been reported regarding the acute impairments induced by a single dose of ?9-THC on verbal and working memory. It is unclear whether they may persist beyond the intoxication state. In the long-term, these impairments seem particularly likely to manifest and may also persist following abstinence if regular and heavy use of cannabis strains high in ?9-THC is started at an early age. Although still at an early stage, studies that employed advanced neuroimaging techniques have started to model the neural underpinnings of the effects of cannabis use and implicate a network of functional and morphological alterations that may moderate the effects of cannabis on memory function. Future experimental and epidemiological studies that take into consideration individual differences, particularly previous cannabis history and demographic characteristics, but also the precise mixture of the ingredients of the consumed cannabis are necessary to clarify the magnitude and the mechanisms by which cannabis-induced memory impairments occur and to elucidate underlying neurobiological mechanisms. PMID:24648785

Schoeler, Tabea; Bhattacharyya, Sagnik

2013-01-01

365

Testing hypotheses about the relationship between cannabis use and psychosis  

Microsoft Academic Search

Aim: To model the impact of rising rates of cannabis use on the incidence and prevalence of psychosis under four hypotheses about the relationship between cannabis use and psychosis. Methods: The study modelled the effects on the prevalence of schizophrenia over the lifespan of cannabis in eight birth cohorts: 1940–1944, 1945–1949, 1950–1954, 1955–1959, 1960–1964, 1965–1969, 1970–1974, 1975–1979. It derived predictions

Louisa Degenhardt; Wayne Hall; Michael Lynskey

2003-01-01

366

Cannabis careers revisited: applying Howard S. Becker's theory to present-day cannabis use.  

PubMed

A considerable part of today's sociological research on recreational drug use is (explicitly or implicitly) inspired by Howard Becker's classical model of deviant careers. The aim of the present paper is to directly apply Becker's theory to empirical data on present-day cannabis use and to suggest a revision of the theory. As part of this, we propose a stretch of the sociological approach represented by Becker and followers in order to include, not only recreational drug use, but also use for which young people have sought treatment. The paper is based on 30 qualitative interviews with young people in treatment for cannabis problems in Copenhagen, Denmark. We suggest a revision of Becker's career model in relation to four aspects: initiation of cannabis use, differentiation between socially integrated and individualised, disintegrated use, social control from non-users, and the users' moral stance on cannabis. A central point of the paper is that social interaction may both motivate cannabis use, as Becker proposed, and serve as a protective factor against extensive, problematic use. PMID:24444848

Järvinen, Margaretha; Ravn, Signe

2014-01-01

367

Whither RDS? An investigation of Respondent Driven Sampling as a method of recruiting mainstream marijuana users  

PubMed Central

Background An important challenge in conducting social research of specific relevance to harm reduction programs is locating hidden populations of consumers of substances like cannabis who typically report few adverse or unwanted consequences of their use. Much of the deviant, pathologized perception of drug users is historically derived from, and empirically supported, by a research emphasis on gaining ready access to users in drug treatment or in prison populations with higher incidence of problems of dependence and misuse. Because they are less visible, responsible recreational users of illicit drugs have been more difficult to study. Methods This article investigates Respondent Driven Sampling (RDS) as a method of recruiting experienced marijuana users representative of users in the general population. Based on sampling conducted in a multi-city study (Halifax, Montreal, Toronto, and Vancouver), and compared to samples gathered using other research methods, we assess the strengths and weaknesses of RDS recruitment as a means of gaining access to illicit substance users who experience few harmful consequences of their use. Demographic characteristics of the sample in Toronto are compared with those of users in a recent household survey and a pilot study of Toronto where the latter utilized nonrandom self-selection of respondents. Results A modified approach to RDS was necessary to attain the target sample size in all four cities (i.e., 40 'users' from each site). The final sample in Toronto was largely similar, however, to marijuana users in a random household survey that was carried out in the same city. Whereas well-educated, married, whites and females in the survey were all somewhat overrepresented, the two samples, overall, were more alike than different with respect to economic status and employment. Furthermore, comparison with a self-selected sample suggests that (even modified) RDS recruitment is a cost-effective way of gathering respondents who are more representative of users in the general population than nonrandom methods of recruitment ordinarily produce. Conclusions Research on marijuana use, and other forms of drug use hidden in the general population of adults, is important for informing and extending harm reduction beyond its current emphasis on 'at-risk' populations. Expanding harm reduction in a normalizing context, through innovative research on users often overlooked, further challenges assumptions about reducing harm through prohibition of drug use and urges consideration of alternative policies such as decriminalization and legal regulation. PMID:20618944

2010-01-01

368

Cannabis en de Relatie tot Schizotypische, Antisociale en Borderline Persoonlijkheidskenmerken.  

E-print Network

??In het huidige onderzoek werd gekeken naar de relatie tussen cannabis-gebruik en drie persoonlijkheidsstoornissen; de antisociale, de borderline en de schizotypische. 119 participanten werden in… (more)

Kramer, M.

2013-01-01

369

Bad trip due to anticholinergic effect of cannabis.  

PubMed

Cannabis in its various forms has been known since time immemorial, the use of which has been rising steadily in India. 'Bad trips' have been documented after cannabis use, manifestations ranging from vague anxiety and fear to profoundly disturbing states of terror and psychosis. Cannabis is known to affect various neurotransmitters, but 'bad trip' due to its anticholinergic effect has never been described in literature to the best of author's knowledge. Hereby, the author describes a case of a young adult male experiencing profound anticholinergic effects after being exposed for the first time in his life to bhang, a local oral preparation of cannabis. PMID:23906840

Mangot, Ajish G

2013-01-01

370

Cannabis smoke condensate II: influence of tobacco on tetrahydrocannabinol levels.  

PubMed

Medicinal cannabis has attracted a lot of attention in recent times. Various forms of administration are used, of which smoking is very common but the least desirable. Smoking cannabis generates a large amount of unwanted side products, of which carcinogenic compounds are the most dangerous. A common practice among recreational drug users, and to a lesser degree patients who uses cannabis as medicine, is to mix the cannabis material with commercially available tobacco in order to increase the burning efficiency of the cigarette and to reduce the overall costs of the cigarette. In this study cannabis material has been mixed with tobacco in order to determine whether tobacco has an influence on the amount of and ratio between tetrahydrocannabinol (THC), cannabigerol (CBG), and cannabinol (CBN) administered while smoking. A small-scale smoking machine has been used and cannabis mixed with various ratios of tobacco was smoked. The trapped smoke was quantitatively analyzed by high-performance liquid chromatography (HPLC) and the amount of THC, CBG, and CBN was determined for each cigarette. We have found that tobacco increases the amount of THC inhaled per gram of cannabis from 32.70 +/- 2.29 mg/g for a 100% cannabis cigarette to 58.90 +/- 2.30 mg/g for a 25% cannabis cigarette. This indicates that tobacco increases the vaporization efficiency of THC by as much as 45% under the conditions tested. PMID:18855154

Van der Kooy, F; Pomahacova, B; Verpoorte, R

2009-02-01

371

Aerobic Exercise Training Reduces Cannabis Craving and Use in Non-Treatment Seeking Cannabis-Dependent Adults  

Microsoft Academic Search

BackgroundCannabis dependence is a significant public health problem. Because there are no approved medications for this condition, treatment must rely on behavioral approaches empirically complemented by such lifestyle change as exercise.AimsTo examine the effects of moderate aerobic exercise on cannabis craving and use in cannabis dependent adults under normal living conditions.DesignParticipants attended 10 supervised 30-min treadmill exercise sessions standardized using

Maciej S. Buchowski; Natalie N. Meade; Evonne Charboneau; Sohee Park; Mary S. Dietrich; Ronald L. Cowan; Peter R. Martin; Antonio Verdejo García

2011-01-01

372

Cigarettes, alcohol, marijuana, other risk behaviors, and American youth  

Microsoft Academic Search

Increases in adolescent marijuana and other drug use have created widespread concern. One theory argues that increased use of cigarettes and alcohol among younger adolescents leads to greater use of marijuana which, in turn, leads to subsequent use of other drugs (e.g. cocaine, heroin, hallucinogens). Detractors of this theory claim that use of these substances is a symptom of a

Jeffrey C. Merrill; Herbert D. Kleber; Michael Shwartz; Hong Liu; Susan R. Lewis

1999-01-01

373

Marijuana use and high school dropout: the influence of unobservables  

Microsoft Academic Search

In this study, we reconsider the relationship between heavy and persistent marijuana use and high school dropout status. Using a unique prospective panel study of over 4500 7th grade students from South Dakota who are followed through high school, we developed propensity score weights to adjust for baseline differences found to exist before marijuana initiation occurs for most students (7th

Daniel F. McCaffrey; Rosalie Liccardo Pacula; Bing Han; Phyllis Ellickson

2010-01-01

374

Marijuana Use and High School Dropout: The Influence of Unobservables  

Microsoft Academic Search

In this study we reconsider the relationship between heavy and persistent marijuana use and high school dropout status using a unique prospective panel study of over 4500 7th grade students from South Dakota who are followed up through high school. Propensity score weighting is used to adjust for baseline differences that are found to exist before marijuana initiation occurs (7th

Daniel F. McCaffrey; Rosalie Liccardo Pacula; Bing Han; Phyllis Ellickson

2008-01-01

375

Long-term effects of marijuana use on the brain.  

PubMed

Questions surrounding the effects of chronic marijuana use on brain structure continue to increase. To date, however, findings remain inconclusive. In this comprehensive study that aimed to characterize brain alterations associated with chronic marijuana use, we measured gray matter (GM) volume via structural MRI across the whole brain by using voxel-based morphology, synchrony among abnormal GM regions during resting state via functional connectivity MRI, and white matter integrity (i.e., structural connectivity) between the abnormal GM regions via diffusion tensor imaging in 48 marijuana users and 62 age- and sex-matched nonusing controls. The results showed that compared with controls, marijuana users had significantly less bilateral orbitofrontal gyri volume, higher functional connectivity in the orbitofrontal cortex (OFC) network, and higher structural connectivity in tracts that innervate the OFC (forceps minor) as measured by fractional anisotropy (FA). Increased OFC functional connectivity in marijuana users was associated with earlier age of onset. Lastly, a quadratic trend was observed suggesting that the FA of the forceps minor tract initially increased following regular marijuana use but decreased with protracted regular use. This pattern may indicate differential effects of initial and chronic marijuana use that may reflect complex neuroadaptive processes in response to marijuana use. Despite the observed age of onset effects, longitudinal studies are needed to determine causality of these effects. PMID:25385625

Filbey, Francesca M; Aslan, Sina; Calhoun, Vince D; Spence, Jeffrey S; Damaraju, Eswar; Caprihan, Arvind; Segall, Judith

2014-11-25

376

Marijuana and Cocaine Effect Expectancies and Drug Use Patterns.  

ERIC Educational Resources Information Center

Content analyzed self-reports from 704 college students and used results to develop Marijuana Effect Expectancy Questionnaire and Cocaine Effect Expectancy Questionnaire. Identified six marijuana expectancies and five cocaine expectancies. Drug effect expectancies distinguished between patterns of nonuse and varying degrees of use of these two…

Schafer, John; Brown, Sandra A.

1991-01-01

377

Addiction Medicine Perspective on the Medicalization of Marijuana  

Microsoft Academic Search

Many medical, ethical, legal and political issues have been raised by legislation in California removing criminal penalties for the medical use of marijuana. The California Society of Addiction Medicine (CSAM) has taken an addiction medicine perspective on the use of marijuana as medicine in an effort to create a neutral framework for dealing with these issues. As part of this

Timmen L. Cermak

1998-01-01

378

State Medical Marijuana Laws: Understanding the Laws and their Limitations  

Microsoft Academic Search

Abstract Since the 1970s, numerous states have had medical marijuana laws. However, public policy makers, activists and the media have given significant attention to the debate regarding allowances for medical marijuana use since the 1996 California and Arizona ballot initiatives. Much of this on-going debate stems from confusion about the various ways states approach the issue. In this paper, we

Rosalie Liccardo Pacula; Jamie F. Chriqui; Deborah A. Reichmann; Yvonne M. Terry-McElrath

379

Altered affective response in marijuana smokers: An FMRI study  

Microsoft Academic Search

More than 94 million Americans have tried marijuana, and it remains the most widely used illicit drug in the nation. Investigations of the cognitive effects of marijuana report alterations in brain function during tasks requiring executive control, including inhibition and decision-making. Endogenous cannabinoids regulate a variety of emotional responses, including anxiety, mood control, and aggression; nevertheless, little is known about

Staci A. Gruber; Jadwiga Rogowska; Deborah A. Yurgelun-Todd

2009-01-01

380

The Effectiveness of Gateway Communications in Anti-Marijuana Campaigns  

Microsoft Academic Search

Successful anti-marijuana messages can be hypothesized to have two types of effects, namely persuasion effects, that is, a change in people's beliefs about using marijuana, and priming effects, that is, a strengthened correlation between beliefs and associated variables such as attitude and intention. This study examined different sets of anti-drug advertisements for persuasion and priming effects. The ads targeted the

MARCO C. YZER; JOSEPH N. CAPPELLA; MARTIN FISHBEIN; ROBERT HORNIK; R. KIRKLAND AHERN

2003-01-01

381

A gateway to nature: Teenagers' narratives on smoking marijuana outdoors  

Microsoft Academic Search

Increasingly, many youth are disconnected from the natural world; rather, they inhabit a technological world. Although experiences in nature have long been a source of fascination, little is known about how youth independently access and make sense of nature. We focus on the experiences of youth who chose to use marijuana in nature. A substance such as marijuana is often

Barbara M. Moffat; Joy L. Johnson; Jean A. Shoveller

2009-01-01

382

Relief-oriented use of marijuana by teens  

Microsoft Academic Search

BACKGROUND: There are indications that marijuana is increasingly used to alleviate symptoms and for the treatment of a variety of medical conditions both physical and psychological. The purpose of this study was to describe the health concerns and problems that prompt some adolescents to use marijuana for therapeutic reasons, and their beliefs about the risks and benefits of the therapeutic

Joan L Bottorff; Joy L Johnson; Barbara M Moffat; Tamsin Mulvogue

2009-01-01

383

The Early Adolescent's Personality and His Style of Marijuana Usage.  

ERIC Educational Resources Information Center

Students in four metropolitan high schools participated in a survey of marijuana use. It was found that the personality traits of these early adolescents were related to the "style" of their marijuana usage, i.e., to the social conditions under which they tended to use the drug. Further, a given personality trait's relationship to the style of…

Blake, Brian F.; And Others

384

The Social Context of Cannabis Use: Relationship to Cannabis Use Disorders and Depressive Symptoms among College Students  

PubMed Central

Few studies have investigated the association between the social context of cannabis use and cannabis use disorder (CUD). This longitudinal study of college students aimed to: develop a social context measure of cannabis use; examine the degree to which social context is associated with the transition from non-problematic cannabis use to CUD; and, examine the association between social context of cannabis use and depressive symptoms. The analytic sample consisted of 322 past-year cannabis users at baseline. Four distinct and internally consistent social context scales were found (i.e., social facilitation, emotional pain, sex-seeking, and peer acceptance). Persistent CUD (meeting DSM-IV criteria for CUD at baseline and twelve months later) was associated with using cannabis in social facilitation or emotional pain contexts, controlling for frequency of cannabis use and alcohol use quantity. Students with higher levels of depressive symptoms were more likely to use cannabis in an emotional pain or sex-seeking context. These findings highlight the importance of examining the social contextual factors relating to substance use among college students. PMID:19497678

Beck, Kenneth H.; Caldeira, Kimberly M.; Vincent, Kathryn B.; O'Grady, Kevin E.; Wish, Eric D.; Arria, Amelia M.

2009-01-01

385

Nefazodone decreases anxiety during marijuana withdrawal in humans  

Microsoft Academic Search

  Abstract\\u000a \\u000a \\u000a Rationale. Symptoms of marijuana withdrawal include increased irritability, depression and anxiety, and decreased sleep quality. Nefazodone,\\u000a which is an antidepressant with sedative properties, may attenuate symptoms of marijuana withdrawal.\\u000a \\u000a \\u000a \\u000a \\u000a Objective. The present within-subject, placebo-controlled study investigated the effects of nefazodone during marijuana withdrawal.\\u000a \\u000a \\u000a \\u000a \\u000a Methods. Marijuana smokers [n=7; averaging 6.0 (±1.3) marijuana cigarettes\\/day, 6.4 (±0.4) days\\/week], not seeking treatment for

Margaret Haney; Carl L. Hart; Amie S. Ward; Richard W. Foltin

2003-01-01

386

What place for ? cannabis extract in MS?  

PubMed

Multiple sclerosis (MS) is a neurological condition that is estimated to affect around 60,000 people in England and Wales, with a lifetime risk in the UK of 1 in 1,000.(1,2) Spasticity (an increase in muscle tone) is a common symptom of MS, resulting in muscle spasms, immobility, disturbed sleep and pain.(3,4) Complex drug combinations are sometimes necessary to manage symptoms of MS, but these are often only partially effective and associated with unacceptable side effects.(5) Cannabis extract containing delta9-tetrahydrocannabinol (dronabinol) and cannabidiol are the principal extracts from the cannabis plant present in a licensed preparation (?Sativex - GW Pharma Ltd), the first cannabinoid preparation to be approved for medical use. Sativex has been licensed "for symptom improvement in adult patients with moderate to severe spasticity due to MS who have not responded adequately to other anti-spasticity medication and who demonstrate clinically significant improvement in spasticity related symptoms during an initial trial of therapy".(6) Here we review the evidence for cannabis extract and its place in the treatment of the condition. PMID:23241565

2012-12-01

387

Effects of risk perception of marijuana use on marijuana use and intentions to use among adolescents in Bogotá, Colombia  

Microsoft Academic Search

BackgroundPerceived risk is a key concept of behavioral theories used to predict substance use among youth and a core component of drug use prevention interventions. The present study aimed to (1) assess degrees of risk perception of regular marijuana use, (2) identify factors associated with risk perception, and (3) explore the associations between perceived risk and marijuana use and intentions

Catalina Lopez-Quintero; Yehuda Neumark

2010-01-01

388

Risk and Vulnerability for Marijuana Use Problems: The Role of Affect Dysregulation  

Microsoft Academic Search

This study examined the moderating effects of impulsivity and affect lability on relations between marijuana use frequency and use consequences. From a sample of 592 undergraduates, 300 marijuana users completed a survey that assessed marijuana problems and the hypothesized risk and vulnerability factors. Affective variables were significantly associated with increased marijuana problems above and beyond the effects of gender and

Jeffrey S. Simons; Kate B. Carey

2002-01-01

389

Performance of heavy marijuana-smoking adolescents on a laboratory measure of motivation  

Microsoft Academic Search

Marijuana smoking produces effects that may persist for hours or days beyond the period of acute intoxication. Despite evidence that adolescence represents a period of heightened exposure to marijuana, little research exists regarding possible impairment in adolescents who smoke marijuana regularly, and none exists regarding basic behavioral processes. In the present study, adolescents who smoked marijuana on a regular basis

Don R. Cherek; Cynthia J. Pietras; Joel L. Steinberg

2005-01-01

390

Variabilit des phnomnes d'interfrence entre Vicia sativa L. et Avena sativa L.. I. Dynamique  

E-print Network

Agronomie Variabilité des phénomènes d'interférence entre Vicia sativa L. et Avena sativa L.. I; Variability of the phenomena of interferences between Vicia sativa L. and Avena sativa L. I. Growth dynamics

Boyer, Edmond

391

Is cannabis a gateway drug? Testing hypotheses about the relationship between cannabis use and the use of other illicit drugs.  

PubMed

We outline and evaluate competing explanations of three relationships that have consistently been found between cannabis use and the use of other illicit drugs, namely, (1) that cannabis use typically precedes the use of other illicit drugs; and that (2) the earlier cannabis is used, and (3) the more regularly it is used, the more likely a young person is to use other illicit drugs. We consider three major competing explanations of these patterns: (1) that the relationship is due to the fact that there is a shared illicit market for cannabis and other drugs which makes it more likely that other illicit drugs will be used if cannabis is used; (2) that they are explained by the characteristics of those who use cannabis; and (3) that they reflect a causal relationship in which the pharmacological effects of cannabis on brain function increase the likelihood of using other illicit drugs. These explanations are evaluated in the light of evidence from longitudinal epidemiological studies, simulation studies, discordant twin studies and animal studies. The available evidence indicates that the association reflects in part but is not wholly explained by: (1) the selective recruitment to heavy cannabis use of persons with pre-existing traits (that may be in part genetic) that predispose to the use of a variety of different drugs; (2) the affiliation of cannabis users with drug using peers in settings that provide more opportunities to use other illicit drugs at an earlier age; (3) supported by socialisation into an illicit drug subculture with favourable attitudes towards the use of other illicit drugs. Animal studies have raised the possibility that regular cannabis use may have pharmacological effects on brain function that increase the likelihood of using other drugs. We conclude with suggestions for the type of research studies that will enable a decision to be made about the relative contributions that social context, individual characteristics, and drug effects make to the relationship between cannabis use and the use of other drugs. PMID:16191720

Hall, Wayne D; Lynskey, Michael

2005-01-01

392

High-performance sport, marijuana, and cannabimimetics.  

PubMed

The prohibition on use of cannabinoids in sporting competitions has been widely debated and continues to be a contentious issue. Information continues to accumulate on the adverse health effects of smoked marijuana and the decrement of performance caused by the use of cannabinoids. The objective of this article is to provide an overview of cannabinoids and cannabimimetics that directly or indirectly impact sport, the rules of sport, and performance of the athlete. This article reviews some of the history of marijuana in Olympic and Collegiate sport, summarizes the guidelines by which a substance is added to the World Anti-Doping Agency Prohibited List, and updates information on the pharmacologic effects of cannabinoids and their mechanism of action. The recently marketed cannabimimetics Spice and K2 are included in the discussion as they activate the same receptors as are activated by THC. The article also provides a view as to why the World Anti-Doping Agency prohibits cannabinoid or cannabimimetic use incompetition and should continue to do so. PMID:22080902

Hilderbrand, Richard L

2011-11-01

393

Long-term effects of cannabis on brain structure.  

PubMed

The dose-dependent toxicity of the main psychoactive component of cannabis in brain regions rich in cannabinoid CB1 receptors is well known in animal studies. However, research in humans does not show common findings across studies regarding the brain regions that are affected after long-term exposure to cannabis. In the present study, we investigate (using Voxel-based Morphometry) gray matter changes in a group of regular cannabis smokers in comparison with a group of occasional smokers matched by the years of cannabis use. We provide evidence that regular cannabis use is associated with gray matter volume reduction in the medial temporal cortex, temporal pole, parahippocampal gyrus, insula, and orbitofrontal cortex; these regions are rich in cannabinoid CB1 receptors and functionally associated with motivational, emotional, and affective processing. Furthermore, these changes correlate with the frequency of cannabis use in the 3 months before inclusion in the study. The age of onset of drug use also influences the magnitude of these changes. Significant gray matter volume reduction could result either from heavy consumption unrelated to the age of onset or instead from recreational cannabis use initiated at an adolescent age. In contrast, the larger gray matter volume detected in the cerebellum of regular smokers without any correlation with the monthly consumption of cannabis may be related to developmental (ontogenic) processes that occur in adolescence. PMID:24633558

Battistella, Giovanni; Fornari, Eleonora; Annoni, Jean-Marie; Chtioui, Haithem; Dao, Kim; Fabritius, Marie; Favrat, Bernard; Mall, Jean-Frédéric; Maeder, Philippe; Giroud, Christian

2014-08-01

394

Pathways from Cannabis to Psychosis: A Review of the Evidence  

PubMed Central

The nature of the relationship between cannabis use (CU) and psychosis is complex and remains unclear. Researchers and clinicians remain divided regarding key issues such as whether or not cannabis is an independent cause of psychosis and schizophrenia. This paper reviews the field in detail, examining questions of causality, the neurobiological basis for such causality and for differential inter-individual risk, the clinical and cognitive features of psychosis in cannabis users, and patterns of course and outcome of psychosis in the context of CU. The author proposes two major pathways from cannabis to psychosis based on a differentiation between early-initiated lifelong CU and a scenario where vulnerable individuals without a lifelong pattern of use consume cannabis over a relatively brief period of time just prior to psychosis onset. Additional key factors determining the clinical and neurobiological manifestation of psychosis as well as course and outcome in cannabis users include: underlying genetic and developmental vulnerability to schizophrenia-spectrum disorders; and whether or not CU ceases or continues after the onset of psychosis. Finally, methodological guidelines are presented for future research aimed at both elucidating the pathways that lead from cannabis to psychosis and clarifying the long-term outcome of the disorder in those who have a history of using cannabis. PMID:24133460

Burns, Jonathan K.

2013-01-01

395

Long-Term Effects of Cannabis on Brain Structure  

PubMed Central

The dose-dependent toxicity of the main psychoactive component of cannabis in brain regions rich in cannabinoid CB1 receptors is well known in animal studies. However, research in humans does not show common findings across studies regarding the brain regions that are affected after long-term exposure to cannabis. In the present study, we investigate (using Voxel-based Morphometry) gray matter changes in a group of regular cannabis smokers in comparison with a group of occasional smokers matched by the years of cannabis use. We provide evidence that regular cannabis use is associated with gray matter volume reduction in the medial temporal cortex, temporal pole, parahippocampal gyrus, insula, and orbitofrontal cortex; these regions are rich in cannabinoid CB1 receptors and functionally associated with motivational, emotional, and affective processing. Furthermore, these changes correlate with the frequency of cannabis use in the 3 months before inclusion in the study. The age of onset of drug use also influences the magnitude of these changes. Significant gray matter volume reduction could result either from heavy consumption unrelated to the age of onset or instead from recreational cannabis use initiated at an adolescent age. In contrast, the larger gray matter volume detected in the cerebellum of regular smokers without any correlation with the monthly consumption of cannabis may be related to developmental (ontogenic) processes that occur in adolescence. PMID:24633558

Battistella, Giovanni; Fornari, Eleonora; Annoni, Jean-Marie; Chtioui, Haithem; Dao, Kim; Fabritius, Marie; Favrat, Bernard; Mall, Jean-Frederic; Maeder, Philippe; Giroud, Christian

2014-01-01

396

Pathways from cannabis to psychosis: a review of the evidence.  

PubMed

The nature of the relationship between cannabis use (CU) and psychosis is complex and remains unclear. Researchers and clinicians remain divided regarding key issues such as whether or not cannabis is an independent cause of psychosis and schizophrenia. This paper reviews the field in detail, examining questions of causality, the neurobiological basis for such causality and for differential inter-individual risk, the clinical and cognitive features of psychosis in cannabis users, and patterns of course and outcome of psychosis in the context of CU. The author proposes two major pathways from cannabis to psychosis based on a differentiation between early-initiated lifelong CU and a scenario where vulnerable individuals without a lifelong pattern of use consume cannabis over a relatively brief period of time just prior to psychosis onset. Additional key factors determining the clinical and neurobiological manifestation of psychosis as well as course and outcome in cannabis users include: underlying genetic and developmental vulnerability to schizophrenia-spectrum disorders; and whether or not CU ceases or continues after the onset of psychosis. Finally, methodological guidelines are presented for future research aimed at both elucidating the pathways that lead from cannabis to psychosis and clarifying the long-term outcome of the disorder in those who have a history of using cannabis. PMID:24133460

Burns, Jonathan K

2013-01-01

397

Barbexaclone abuse in a cannabis ex-user.  

PubMed

Abuse of drugs including addictive ingredients is common among patients with initial addiction history. This article reports a patient who had experienced a panic attack due to cannabis intoxication and has began to abuse an antiepileptic drug barbexaclone after he had quitted cannabis. PMID:21038181

Darc?n, Asli Enez; Dilbaz, Nesrin; Okay, Ihsan Tuncer

2010-10-01

398

Cannabis, the mind and society: the hash realities  

Microsoft Academic Search

Cannabis has been known for at least 4,000 years to have profound effects on the mind — effects that have provoked dramatically divergent attitudes towards it. Some societies have regarded cannabis as a sacred boon for mankind that offers respite from the tribulations of everyday life, whereas others have demonized it as inevitably leading to 'reefer madness'. The debate between

Paul D. Morrison; Cécile Henquet; Marta Di Forti; Robin M. Murray

2007-01-01

399

State of the Art Treatments for Cannabis Dependence  

PubMed Central

Synopsis This article reviews established and emerging treatment options for cannabis dependence. Cannabis dependence poses some distinct challenges for treatment providers. The evolving sociocultural context of cannabis use for medical purposes, policy liberalization, and societal normalization has contributed to decreased perceived risk and increased acceptability of use. Simultaneously, the comparatively lower “severity” of cannabis-associated consequences makes it more difficult for some users to recognize the impact of their use and establish an enduring commitment to change. As a result, many treatment seekers are reluctant to accept traditional abstinence-based goals. Among treatment providers, consensus has not been established about the value of non-abstinence goals, such as moderation and harm reduction. Notwithstanding these challenges, the high prevalence of cannabis dependence, its strong association with co-morbid mental health problems, and the difficulty of achieving cannabis cessation ensure that many psychiatrists will face patients with cannabis dependence. While no pharmacotherapy has been approved for cannabis dependence, a number of promising approaches are in development. Psychotherapy studies are establishing a number of evidence-based models and techniques in the treatment resources for patients in need. PMID:22640758

Danovitch, Itai; Gorelick, David A.

2012-01-01

400

Neuronal substrates and functional consequences of prenatal cannabis exposure.  

PubMed

Cannabis remains one of the world's most widely used substance of abuse amongst pregnant women. Trends of the last 50 years show an increase in popularity in child-bearing women together with a constant increase in cannabis potency. In addition, potent herbal "legal" highs containing synthetic cannabinoids that mimic the effects of cannabis with unknown pharmacological and toxicological effects have gained rapid popularity amongst young adults. Despite the surge in cannabis use during pregnancy, little is known about the neurobiological and psychological consequences in the exposed offspring. In this review, we emphasize the importance of maternal programming, defined as the intrauterine presentation of maternal stimuli to the foetus, in neurodevelopment. In particular, we focus on cannabis-mediated maternal adverse effects, resulting in direct central nervous system alteration or sensitization to late-onset chronic and neuropsychiatric disorders. We compare clinical and preclinical experimental studies on the effects of foetal cannabis exposure until early adulthood, to stress the importance of animal models that permit the fine control of environmental variables and allow the dissection of cannabis-mediated molecular cascades in the developing central nervous system. In sum, we conclude that preclinical experimental models confirm clinical studies and that cannabis exposure evokes significant molecular modifications to neurodevelopmental programs leading to neurophysiological and behavioural abnormalities. PMID:24793873

Calvigioni, Daniela; Hurd, Yasmin L; Harkany, Tibor; Keimpema, Erik

2014-10-01

401

Cannabis and tobacco smoke are not equally carcinogenic  

Microsoft Academic Search

More people are using the cannabis plant as modern basic and clinical science reaffirms and extends its medicinal uses. Concomitantly, concern and opposition to smoked medicine has occurred, in part due to the known carcinogenic consequences of smoking tobacco. Are these reactions justified? While chemically very similar, there are fundamental differences in the pharmacological properties between cannabis and tobacco smoke.

Robert Melamede

2005-01-01

402

Cannabis, motivation, and life satisfaction in an internet sample  

Microsoft Academic Search

Although little evidence supports cannabis-induced amotivational syndrome, sources continue to assert that the drug saps motivation 1, which may guide current prohibitions. Few studies report low motivation in chronic users; another reveals that they have higher subjective wellbeing. To assess differences in motivation and subjective wellbeing, we used a large sample (N = 487) and strict definitions of cannabis use

Sara Smucker Barnwell; Mitch Earleywine; Rand Wilcox

2006-01-01

403

Adolescents Initiating Cannabis Use: Cultural Opposition or Poor Mental Health?  

ERIC Educational Resources Information Center

Investigated possible links between normative and political opposition, mental health, and the use of cannabis in prospective longitudinal study of Norwegian adolescents (n=1,311). Findings indicated that the group that experimented with cannabis was mainly characterized by political and normative "oppositional" engagement, but heavy users also…

Pedersen, Willy

1990-01-01

404

The short-term consequences of early onset cannabis use  

Microsoft Academic Search

The associations between early onset (prior to 15 years of age) cannabis use and rates of mental health or adjustment problems during the period from 15 to 16 years of age were studied in a New Zealand birth cohort. Early onset cannabis users were at increased risks of later substance use behaviors, conduct\\/oppositional disorders, juvenile offending, severe truancy, school dropout,

David M. Fergusson; Michael T. Lynskey; L. John Horwood

1996-01-01

405

Chemistry and Analysis of Phytocannabinoids and Other Cannabis Constituents  

Microsoft Academic Search

The Cannabis plant and its products consist of an enormous variety of chemicals. Some of the 483 compounds identified are unique to Cannabis, for example, the more than 60 cannabinoids, whereas the terpenes, with about 140 members forming the most abundant class,\\u000a are widespread in the plant kingdom. The term “cannabinoids” [note: “ ” represents a group of C21 terpenophenolic

Rudolf Brenneisen

406

Neuropsychological Performance in Long-term Cannabis Users  

Microsoft Academic Search

Background: Although cannabis is the most widely used illicit drug in the United States, its long-term cognitive effects remain inadequately studied. Methods: We recruited individuals aged 30 to 55 years in 3 groups: (1) 63 current heavy users who had smoked cannabis at least 5000 times in their lives and who were smoking daily at study entry; (2) 45 former

Harrison G. Pope; Amanda J. Gruber; James I. Hudson; Marilyn A. Huestis; Deborah Yurgelun-Todd

2001-01-01

407

Characterization and antimicrobial activity of essential oils of industrial hemp varieties ( Cannabis sativa L.)  

Microsoft Academic Search

The present study focused on inhibitory activity of freshly extracted essential oils from three legal (THC<0.2% w\\/v) hemp varieties (Carmagnola, Fibranova and Futura) on microbial growth. The effect of different sowing times on oil composition and biological activity was also evaluated. Essential oils were distilled and then characterized through the gas chromatography and gas chromatography-mass spectrometry. Thereafter, the oils were

Lorenzo Nissen; Alessandro Zatta; Ilaria Stefanini; Silvia Grandi; Barbara Sgorbati; Bruno Biavati; Andrea Monti

2010-01-01

408

Carbohydrate components and crystalline structure of organosolv hemp (Cannabis sativa L.) bast fibers pulp.  

PubMed

Changes in carbohydrate components and crystalline structure of hemp bast fibers during organosolv pulping were investigated by X-ray diffractometry, FT-IR spectroscopy and high performance liquid chromatography (HPLC). The reasons for defibrillation and beating problems with organosolv hemp bast fiber pulp were investigated with reference to these properties of pulp samples. Hemp bast fibers and organosolv pulp samples had low hemicellulose contents and high cellulose contents. It was found that the disorder parameter of cellulose in hemp bast fibers was very low, when crystalline cellulose ratio was high and the crystalline structure of cellulose in hemp bast fibers was very stable. These properties affected defibrillation and beating of organosolv hemp bast fibers pulp negatively. PMID:16757165

Gümü?kaya, Esat; Usta, Mustafa; Balaban, Mualla

2007-02-01

409

Kinetics of Enzyme Inhibition and Antihypertensive Effects of Hemp Seed ( Cannabis sativa L.) Protein Hydrolysates  

Microsoft Academic Search

The aim of this study was to determine the antihypertensive effects of enzymatic hemp seed protein hydrolysate (HPH) and its\\u000a peptide fractions. Hemp seed protein isolate was digested by the sequential action of pepsin and pancreatin to mimic gastrointestinal\\u000a digestion in human beings. The resultant HPH was separated by membrane ultrafiltration into peptide fractions with different\\u000a sizes (P < 0.05) in vitro

Abraham T. Girgih; Chibuike C. Udenigwe; Huan Li; Abayomi P. Adebiyi; Rotimi E. Aluko

410

Estimation of Cannabis sativa L. Tissue Culture Conditions Essential for Callus Induction and Plant Regeneration  

Microsoft Academic Search

The effects of different combinations of plant growth regulators on callus induction and plant regeneration were observed in three Polish monoecious hemp cultivars (Bialobrzeskie, Beniko, Silesia). Callus was induced from different explant sources (fragment of cotyledons, stems, roots) on Daria ind+ medium. There was no considerable difference noticed in callus induction between tested cultivars and explants. However, callus obtained from

K. Wielgus; A. Luwanska; W. Lassocinski; Z. Kaczmarek

2008-01-01

411

Improving enzymatic hydrolysis of industrial hemp ( Cannabis sativa L.) by electron beam irradiation  

NASA Astrophysics Data System (ADS)

The electron beam irradiation was applied as a pretreatment of the enzymatic hydrolysis of hemp biomass with doses of 150, 300 and 450 kGy. The higher irradiation dose resulted in the more extraction with hot-water extraction or 1% sodium hydroxide solution extraction. The higher solubility of the treated sample was originated from the chains scission during irradiation, which was indirectly demonstrated by the increase of carbonyl groups as shown in diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) spectra. The changes in the micro-structure of hemp resulted in the better response to enzymatic hydrolysis with commercial cellulases (Celluclast 1.5L and Novozym 342). The improvement in enzymatic hydrolysis by the irradiation was more evident in the hydrolysis of the xylan than in that of the cellulose.

Shin, Soo-Jeong; Sung, Yong Joo

2008-09-01

412

Applying a Social Determinants of Health Perspective to Early Adolescent Cannabis Use--An Overview  

ERIC Educational Resources Information Center

Cannabis is the most widely used illicit drug in the world. Although the risk of problematic cannabis use is relatively low, the lifetime prevalence of dependence is greater than for all other illicit drugs. As such, the population burden of problematic cannabis use warrants attention. Many health and psychosocial risks associated with cannabis

Hyshka, Elaine

2013-01-01

413

Rural doctors' attitudes to and knowledge of medicinal cannabis.  

PubMed

The use of cannabis for medical purposes remains controversial. Since support from general practitioners would be needed for the successful operation of a legalised prescription regime, New South Wales Northern Rivers general practitioners were surveyed on their attitudes to and knowledge of medicinal cannabis. A representative random sample of general practitioners, stratified by age and gender, was derived and interviewed. Results indicated generally high levels of knowledge of cannabis's medical uses. The mean number of patients seen in 2004 with medicinal cannabis-treatable conditions was 66.8, with chronic pain patients accounting for 36.7. Overwhelming majorities of respondents reported they would prescribe medicinal cannabis if it were legal, professionally supported and backed by research and that they would approve of clinical trials and a legalised regulatory scheme under such conditions. These results suggest the need to conduct a Statewide general practitioners' survey to confirm or refute the present findings. PMID:16937787

Irvine, Graham

2006-08-01

414

Neural Effects of Positive and Negative Incentives during Marijuana Withdrawal  

PubMed Central

In spite of evidence suggesting two possible mechanisms related to drug-seeking behavior, namely reward-seeking and harm avoidance, much of the addiction literature has focused largely on positive incentivization mechanisms associated with addiction. In this study, we examined the contributing neural mechanisms of avoidance of an aversive state to drug-seeking behavior during marijuana withdrawal. To that end, marijuana users were scanned while performing the monetary incentive delay task in order to assess positive and negative incentive processes. The results showed a group x incentive interaction, such that marijuana users had greater response in areas that underlie reward processes during positive incentives while controls showed greater response in the same areas, but to negative incentives. Furthermore, a negative correlation between withdrawal symptoms and response in the amygdala during negative incentives was found in the marijuana users. These findings suggest that although marijuana users have greater reward sensitivity and less harm avoidance than controls, that attenuated amygdala response, an area that underlies fear and avoidance, was present in marijuana users with greater marijuana withdrawal symptoms. This is concordant with models of drug addiction that involve multiple sources of reinforcement in substance use disorders, and suggests the importance of strategies that focus on respective mechanisms. PMID:23690923

Filbey, Francesca M.; Dunlop, Joseph; Myers, Ursula S.

2013-01-01

415

Marijuana and workplace safety: an examination of urine drug tests.  

PubMed

Although the decriminalization of recreational marijuana and medical marijuana laws provide a compassionate answer for treatment-related issues in patients' lives, they leave questions open as to the impact on other realms of life, such as employment and safety. This is a case-control study comparing the proportion of marijuana positive urine specimens for post-accident verses random samples. The marijuana concentration of each sample underwent creatinine normalization to account for in vivo dilution. Any sample that tested positive for one or more substances other than marijuana was eliminated from the study. The prevalence of marijuana violations, the odds ratio and 95% confidence interval of accident involvement and the population attributable risk were calculated. A two-by-two table was created with the remaining data and the data were used to calculate the odds ratio, resulting in a value of 0.814 with a 95% confidence interval between 0.625 and 1.060. The Fisher exact probability test generated a 2-tailed P of .139. The subsequent population attributable risk was found to be -1.83%. These findings fail to reject the null hypothesis, and this study failed to demonstrate a statistically significant difference between the numbers of laboratory positive marijuana urine drug tests for a group of random drug tests compared with a group of post-accident drug tests. PMID:24467478

Price, James W

2014-01-01

416

The Adolescent Community Reinforcement Approach for Adolescent Cannabis Users, Cannabis Youth Treatment (CYT) Series, Volume 4.  

ERIC Educational Resources Information Center

This publication was written for therapists and their supervisors who may want to implement the adolescent community reinforcement approach intervention, which was one of the five interventions tested by the Center for Substance Abuse Treatment's (CSAT's) Cannabis Youth Treatment (CYT) Project. The CYT Project provided funding to support a study…

Godley, Susan Harrington; Meyers, Robert J.; Smith, Jane Ellen; Karvinen, Tracy; Titus, Janet C.; Godley, Mark D.; Dent, George; Passetti, Lora; Kelberg, Pamela

417

The interactive effects of emotional clarity and cognitive reappraisal on problematic cannabis use among medical cannabis users  

E-print Network

among medical cannabis users Matthew Tyler Boden a, , James J. Gross b , Kimberly A. Babson a,c , Marcel, PA 19104, United States H I G H L I G H T S Current debates on legalization of cannabis for medical reasons not informed by data. Investigated two factors that may lead to problematic use in medical

Gross, James J.

418

Believability of Messages about Cannabis, Cocaine and Heroin among Never-Triers, Trier-Rejecters and Current Users of Cannabis  

ERIC Educational Resources Information Center

This paper examines the believability of strong warnings about the negative consequences of drug use among young adults in Australia who have never tried, currently use, or have tried and rejected cannabis. It finds that the strong warnings about cannabis are generally believed by never-triers. The same warnings are perceived by current users as…

Jones, Sandra C.; Rossiter, John R.

2004-01-01

419

Believability of messages about cannabis, cocaine and heroin among never-triers, trier-rejecters and current users of cannabis  

Microsoft Academic Search

This paper examines the believability of strong warnings about the negative consequences of drug use among young adults in Australia who have never tried, currently use, or have tried and rejected cannabis. It finds that the strong warnings about cannabis are generally believed by never-triers. The same warnings are perceived by current users as only slightly believable. Surprisingly, but also

Sandra C. Jones; John R. Rossiter

2004-01-01

420

Psychometric Properties of a Valuations Scale for the Marijuana Effect Expectancies Questionnaire  

PubMed Central

Given that marijuana remains the most commonly used illicit substance, identification of the role of potentially malleable cognitive factors in marijuana-related behaviors remains an important goal. The Marijuana Effect Expectancies Questionnaire (MEEQ; Schafer & Brown, 1991) assesses marijuana effect expectancies that are differentially related to marijuana use and use-related problems. Evaluation of the desirability of marijuana effect expectancies may provide additional information regarding cognitions related to marijuana use behaviors. The present study examined the psychometric properties of the Marijuana Effect Expectancy Questionnaire-Valuations Scale (MEEQ-V) which was developed for this study to assess the desirability of marijuana effect expectancies. The sample was comprised of 925 (73.0% female) undergraduate participants, 41.9% of whom endorsed lifetime marijuana use and 24.7% of whom reported current (past three-month) use. The MEEQ-V scales demonstrated adequate internal consistency. Most (but not all) MEEQ-V scales were correlated with their corresponding MEEQ scale. There was some support for convergent validity. MEEQ-V scales were differentially related to frequency of marijuana use and use-related problems. Most MEEQ-V scales were related to frequency of marijuana use above and beyond variance attributable to corresponding MEEQ scales. Results suggest that assessment of desirability of marijuana’s effects could provide unique and important information about cognitions related to marijuana use behaviors. PMID:23254209

Buckner, Julia D.; Ecker, Anthony H.; Welch, Katherine D.

2013-01-01

421

Media exposure and marijuana and alcohol use among adolescents.  

PubMed

We aimed to determine which media exposures are most strongly associated with marijuana and alcohol use among adolescents. In 2004, we surveyed 1,211 students at a large high school in suburban Pittsburgh regarding substance use, exposure to entertainment media, and covariates. Of the respondents, 52% were female, 8% were non-White, 27% reported smoking marijuana, and 60% reported using alcohol. They reported average exposure to 8.6 hr of media daily. In adjusted models, exposure to music was independently associated with marijuana use, but exposure to movies was independently associated with alcohol use. Implications, limitations, and suggestions for further research are discussed. PMID:19306219

Primack, Brian A; Kraemer, Kevin L; Fine, Michael J; Dalton, Madeline A

2009-01-01

422

Media Exposure and Marijuana and Alcohol Use Among Adolescents  

PubMed Central

We aimed to determine which media exposures are most strongly associated with marijuana and alcohol use among adolescents. In 2004, we surveyed 1,211 students at a large high school in suburban Pittsburgh regarding substance use, exposure to entertainment media, and covariates. Of the respondents, 52% were female, 8% were non-White, 27% reported smoking marijuana, and 60% reported using alcohol. They reported average exposure to 8.6 hr of media daily. In adjusted models, exposure to music was independently associated with marijuana use, but exposure to movies was independently associated with alcohol use. Implications, limitations, and suggestions for further research are discussed. PMID:19306219

PRIMACK, BRIAN A.; KRAEMER, KEVIN L.; FINE, MICHAEL J.; DALTON, MADELINE A.

2010-01-01

423

The interactive effects of emotional clarity and cognitive reappraisal on problematic cannabis use among medical cannabis users.  

PubMed

This study examined whether emotional clarity (i.e., the extent to which one can identify and understand the type and source of emotions one experiences) and cognitive reappraisal (i.e., altering how potentially emotion-eliciting situations are construed to change their emotional impact) would individually or jointly be associated with problematic cannabis use among individuals receiving cannabis for medical reasons (n=153). Findings indicated that problematic cannabis use was predicted by the interaction between emotional clarity and cognitive reappraisal. In particular, low levels of emotional clarity combined with high levels of cognitive reappraisal predicted problematic cannabis use. The current study is the first to demonstrate the interactive effects of emotional clarity and the use of cognitive reappraisal in predicting substance use disorder outcomes. Such findings are important given the lack of empirical data demonstrating for whom and for which conditions cannabis is either beneficial or detrimental. PMID:23254215

Boden, Matthew Tyler; Gross, James J; Babson, Kimberly A; Bonn-Miller, Marcel O

2013-03-01

424

The Effect of Marijuana Scenes in Anti-marijuana Public Service Announcements on Adolescents’ Evaluation of Ad Effectiveness  

PubMed Central

This study explored the possible negative impact of a specific ad feature—marijuana scenes—on adolescents’ perception of ad effectiveness. A secondary data analysis was conducted on adolescents’ evaluations of 60 anti-marijuana public service announcements (PSAs) that were a part of national and state anti-drug campaigns directed at adolescents. The major finding of the study was that marijuana scenes in anti-marijuana PSAs negatively affected ad liking and thought valence toward the ads among adolescents who are at higher levels of risk for marijuana use. This negative impact was not reversed in the presence of strong anti-marijuana arguments. The results may be used to partially explain the lack of effectiveness of the anti-drug media campaign. It may also help us design more effective anti-marijuana PSAs by isolating adverse elements in the ads that may elicit boomerang effects in the target population. Limitations of the study and future directions were discussed. PMID:19735026

Kang, Yahui; Cappella, Joseph N.; Fishbein, Martin

2014-01-01

425

Arrests and convictions for cannabis related offences in a New Zealand birth cohort  

Microsoft Academic Search

Aims: To examine the associations between the use of cannabis and arrest\\/conviction for cannabis related offences. Methods: Data on cannabis use and arrests\\/convictions for cannabis related offences were gathered during the course of a 21-year longitudinal study of a birth cohort of Christchurch (New Zealand) born children (N=983). Information on cannabis use, arrests and convictions was gathered over the period

D. M Fergusson; N. R Swain-Campbell; L. J Horwood

2003-01-01

426

Patterns of medical marijuana use among individuals sampled from medical marijuana dispensaries in los angeles.  

PubMed

Abstract The proliferation of medical marijuana (MM) dispensaries has led to concerns that they will lead to more widespread use of marijuana. The aim of the current study was to collect descriptive data on individuals using MM dispensaries in Los Angeles County. A mixed-method approach was employed that consisted of focus groups with 30 individuals and a survey of dispensary users (N = 182) in Los Angeles County. Differences between younger (less than 30 years old) and older individuals were examined in the survey sample. Most individuals in both samples had initiated marijuana use in adolescence. Nearly one-half of survey respondents had indications of risky alcohol use and one-fifth reported recent use of illicit drugs or misuse of prescription medications. Younger individuals had higher rates of tobacco use, visited dispensaries more frequently, and had more socially embedded patterns of use, but they were similar to older individuals in terms of their reasons for use. Nearly all participants believed that MM was beneficial in treating their health problems, although 65% reported symptoms of psychological distress in the past year. Interventions aimed at MM users should stress the related effects of tobacco and risky alcohol use as well as mental health needs. PMID:25188696

Grella, Christine E; Rodriguez, Luz; Kim, Tina

2014-01-01

427

Adolescent use and misuse of marijuana.  

PubMed

Substance use by adolescents and young adults continues to be a serious problem. Marijuana remains the most commonly used illicit substance with close to 50% of high school seniors admitting use at some time. Each year 2.6 million individuals in this country become new users and most are under 19 years old. Individuals who provide health care services to this age group must have an understanding of the drug, its pharmacokinetics, and the many short- and long-term adverse effects. Familiarity with risk factors associated with initiating use can be helpful in screening older children and targeting anticipatory guidance toward those most likely to benefit. This article reviews these issues and includes commentary on a recently published review of treatment programs. PMID:16814696

Foley, John D

2006-06-01

428

Hypothesizing that Marijuana Smokers are at a Significantly Lower Risk of Carcinogenicity Relative to Tobacco-Non-Marijuana Smokers: Evidenced Based on Statistical Reevaluation of Current Literature  

Microsoft Academic Search

A hypothetical link between marijuana smoking and cancer has been established based on a number of misleading assumptions. However, recent studies tend to suggest, if anything, an inverse association between marijuana use and cancers. To test the hypothesis that marijuana smoking significantly lowers the risk of developing cancer in humans, we analyzed published data from a prospective cohort study on

Amanda L. C. Chen; Thomas J. H. Chen; Eric R. Braverman; Vanessa Acuri; Mallory Kerner; Michael Varshavskiy; Dasha Braverman; William B. Downs; Seth H. Blum; Kimberly Cassel; Kenneth Blum

2008-01-01

429

Associations of marijuana use and sex-related marijuana expectancies with HIV/STD risk behavior in high-risk adolescents  

PubMed Central

Multiple studies suggest an association of marijuana use with increased rates of sexual risk behavior and sexually transmitted diseases (STDs). Most studies have focused on global associations of marijuana use with sexual risk outcomes and few have examined relevant cognitive variables. Adolescents in the juvenile justice system are at elevated risk for HIV/STDs and preliminary evidence suggests that marijuana is a potentially important cofactor for sexual risk behavior in this population. This study evaluated global, situational and event-level associations of marijuana use and sex-related marijuana expectancies with sexual risk outcomes in a large, racially diverse sample of adjudicated youth (n = 656, 66% male, mean age = 16.7 years). Cross-sectional and prospective analyses identified associations of marijuana use and dependence symptoms with sexual risk outcomes, including lower frequency of condom use and higher STD incidence. Stronger sex-related marijuana expectancies predicted greater intentions for and frequency of marijuana use in sexual situations. In event-level analyses that controlled for alcohol, marijuana use predicted a significantly decreased likelihood of condom use; this association was moderated by sex-related marijuana expectancies. Mediation analyses suggested that behavioral intentions partly accounted for the prospective association of expectancies with marijuana use before sex. These results provide further evidence that marijuana use is a potentially important cofactor for HIV/STD transmission in high-risk adolescents and suggest that cognitive factors could be important for characterizing this association. PMID:20853925

Hendershot, Christian S.; Magnan, Renee E.; Bryan, Angela D.

2010-01-01

430

Relations Between Anxiety Sensitivity, Distress Tolerance, and Fear Reactivity to Bodily Sensations to Coping and Conformity Marijuana Use Motives Among Young Adult Marijuana Users  

Microsoft Academic Search

The present investigation examines anxiety sensitivity, distress tolerance, and fear reactivity to bodily sensations in relation to Coping and Conformity marijuana use motives among a sample of young adult marijuana users (n = 135; 46.7% women; Mage = 20.45, SD = 5.0). After controlling for current marijuana use frequency (past 30 days), daily cigarette smoking rate, average volume of alcohol

Michael J. Zvolensky; Erin C. Marshall; Kirsten Johnson; Julianna Hogan; Amit Bernstein; Marcel O. Bonn-Miller

2009-01-01

431

Medical marijuana use for chronic pain: risks and benefits.  

PubMed

Questions from patients about medical marijuana use for chronic pain are becoming more common. The information in this report will help patients understand the potential risks and benefits of using this substance for painful conditions. PMID:22448949

Greenwell, Garth T

2012-01-01

432

Psychomotor Function in Chronic Daily Cannabis Smokers during Sustained Abstinence  

PubMed Central

Background The present study assessed psychomotor function in chronic, daily cannabis smokers during 3 weeks continuously monitored abstinence on a secure research unit. We hypothesized that psychomotor performance would improve during abstinence of chronic, daily cannabis smokers. Methodology/Principal Findings Performance on the critical tracking (CTT) and divided attention (DAT) tasks was assessed in 19 male chronic, daily cannabis smokers at baseline and after 8, 14–16 and 21–23 days of continuously monitored abstinence. Psychomotor performance was compared to a control group of non-intoxicated occasional drug users. Critical frequency (?c) of the CTT and tracking error and control losses of the DAT were the primary outcome measures. Results showed that chronic cannabis smokers’ performance on the CTT (p<0.001) and the DAT (p<0.001) was impaired during baseline relative to the comparison group. Psychomotor performance in the chronic cannabis smokers improved over 3 weeks of abstinence, but did not recover to equivalent control group performance. Conclusions/Significance Sustained cannabis abstinence moderately improved critical tracking and divided attention performance in chronic, daily cannabis smokers, but impairment was still observable compared to controls after 3 weeks of abstinence. Between group differences, however, need to be interpreted with caution as chronic smokers and controls were not matched for education, social economic status, life style and race. PMID:23301031

Bosker, Wendy M.; Karschner, Erin L.; Lee, Dayong; Goodwin, Robert S.; Hirvonen, Jussi; Innis, Robert B.; Theunissen, Eef L.; Kuypers, Kim P. C.

2013-01-01

433

Marijuana Use and Risk of Oral Squamous Cell Carcinoma  

Microsoft Academic Search

Previous laboratory investigations, case reports, and a hospital-based case-control study have suggested that marijuana use may be a risk factor for squamous cell head and neck cancer. We conducted a population- based case-control study to determine whether marijuana use is associated with the development of oral squamous cell carcinoma (OSCC). Case subjects (n 407) were 18 - 65-year-old residents of

Karin A. Rosenblatt; Janet R. Daling; Chu Chen; Karen J. Sherman; Stephen M. Schwartz

2004-01-01

434

Decriminalization and Marijuana Smoking Prevalence: Evidence from Australia  

Microsoft Academic Search

This paper uses the 2001 wave of National Drug Strategy Household Survey (NDSHS) to assess the impact of marijuana decriminalization policy on marijuana smoking prevalence in Australia. Both parametric and non-parametric methods are used. The parametric approach postulates an endogenous probit switching model and its nested binary probit, endogenous bivariate probit and two-part models to estimate this impact. The non-parametric

Kannika Damrongplasit; Cheng Hsiao; Xueyan Zhao

2006-01-01

435

High on Life? Medical Marijuana Laws and Suicide  

Microsoft Academic Search

Using state-level data for the period 1990 through 2007, we estimate the effect of legalizing medical marijuana on suicide rates. Our results suggest that the passage of a medical marijuana law is associated with an almost 5 percent reduction in the total suicide rate, an 11 percent reduction in the suicide rate of 20- through 29-year-old males, and a 9

D. Mark Anderson; Daniel I. Rees; Joseph J. Sabia

2012-01-01

436

Marijuana Withdrawal in Humans: Effects of Oral THC or Divalproex  

Microsoft Academic Search

Abstinence following daily marijuana use can produce a withdrawal syndrome characterized by negative mood (eg irritability, anxiety, misery), muscle pain, chills, and decreased food intake. Two placebo-controlled, within-subject studies investigated the effects of a cannabinoid agonist, delta-9-tetrahydrocannabinol (THC: Study 1), and a mood stabilizer, divalproex (Study 2), on symptoms of marijuana withdrawal. Participants (n=7\\/study), who were not seeking treatment for

Margaret Haney; Carl L Hart; Suzanne K Vosburg; Jennifer Nasser; Andrew Bennett; Carlos Zubaran; Richard W Foltin

2004-01-01

437

Expectancies and marijuana use frequency and severity among young females  

Microsoft Academic Search

This study examined associations between the endorsement of drug use expectancies and the frequency and severity of marijuana use in a community sample of 332 women aged 18–24years who were not explicitly seeking treatment for their marijuana use. Participants were enrolled in a larger intervention study of motivational interviewing for various health behaviors and provided self-reports of their current and

Jumi Hayaki; Claire E. Hagerty; Debra S. Herman; Marcel A. de Dios; Bradley J. Anderson; Michael D. Stein

2010-01-01

438

Psychometric properties of a valuations scale for the Marijuana Effect Expectancies Questionnaire.  

PubMed

Given that marijuana remains the most commonly used illicit substance, identification of the role of potentially malleable cognitive factors in marijuana-related behaviors remains an important goal. The Marijuana Effect Expectancies Questionnaire (MEEQ; Schafer & Brown, 1991) assesses marijuana effect expectancies that are differentially related to marijuana use and use-related problems. Evaluation of the desirability of marijuana effect expectancies may provide additional information regarding cognitions related to marijuana use behaviors. The present study examined the psychometric properties of the Marijuana Effect Expectancy Questionnaire-Valuations Scale (MEEQ-V) which was developed for this study to assess the desirability of marijuana effect expectancies. The sample was comprised of 925 (73.0% female) undergraduate participants, 41.9% of whom endorsed lifetime marijuana use and 24.7% of whom reported current (past three-month) use. The MEEQ-V scales demonstrated adequate internal consistency. Most (but not all) MEEQ-V scales were correlated with their corresponding MEEQ scale. There was some support for convergent validity. MEEQ-V scales were differentially related to frequency of marijuana use and use-related problems. Most MEEQ-V scales were related to frequency of marijuana use above and beyond variance attributable to corresponding MEEQ scales. Results suggest that assessment of desirability of marijuana's effects could provide unique and important information about cognitions related to marijuana use behaviors. PMID:23254209

Buckner, Julia D; Ecker, Anthony H; Welch, Katherine D

2013-03-01

439

Development and Preliminary Validation of a Comprehensive Marijuana Motives Questionnaire*  

PubMed Central

Objective: Relatively little research has evaluated motives for using marijuana based on users' self-reported reasons. This article details the construction and psychometric validation of a new marijuana motives questionnaire. Method: Participants included 346 marijuana-using college students who completed online assessments regarding their motives for, frequency of, and problems associated with their marijuana use. Results: Exploratory and confirmatory factor analysis supported a 12-factor scale, including the following: (1) Enjoyment, (2) Conformity, (3) Coping, (4) Experimentation, (5) Boredom, (6) Alcohol, (7) Celebration, (8) Altered Perception, (9) Social Anxiety, (10) Relative Low Risk, (11) Sleep/Rest, and (12) Availability. Regression results indicated enjoyment, boredom, altered perception, relative low-risk, and sleep/rest were each uniquely associated with greater frequency of use. Experimentation and availability motives were associated with less use. After accounting for use, coping and sleep/rest were associated with significantly more consequences whereas enjoyment was associated with fewer consequences. Additional results comparing the scale to an existing marijuana motives measure indicated comparatively good convergent validity. Conclusions: Emerging adult college students may have several different reasons for using marijuana, which are uniquely related to use and negative consequences. Results are considered in terms of their implications for brief interventions. PMID:19261240

Lee, Christine M.; Neighbors, Clayton; Hendershot, Christian S.; Grossbard, Joel R.

2009-01-01

440

Medical marijuana laws and suicides by gender and age.  

PubMed

Objectives. We estimated the association between legalizing medical marijuana and suicides. Methods. We obtained state-level suicide data from the National Vital Statistics System's Mortality Detail Files for 1990-2007. We used regression analysis to examine the association between medical marijuana legalization and suicides per 100?000 population. Results. After adjustment for economic conditions, state policies, and state-specific linear time trends, the association between legalizing medical marijuana and suicides was not statistically significant at the .05 level. However, legalization was associated with a 10.8% (95% confidence interval [CI]?=?-17.1%, -3.7%) and 9.4% (95% CI?=?-16.1%, -2.4%) reduction in the suicide rate of men aged 20 through 29 years and 30 through 39 years, respectively. Estimates for females were less precise and sensitive to model specification. Conclusions. Suicides among men aged 20 through 39 years fell after medical marijuana legalization compared with those in states that did not legalize. The negative relationship between legalization and suicides among young men is consistent with the hypothesis that marijuana can be used to cope with stressful life events. However, this relationship may be explained by alcohol consumption. The mechanism through which legalizing medical marijuana reduces suicides among young men remains a topic for future study. PMID:24432945

Anderson, D Mark; Rees, Daniel I; Sabia, Joseph J

2014-12-01

441

The ethics of medical marijuana: government restrictions vs. medical necessity.  

PubMed

Marijuana is listed by the Drug Enforcement Agency (DEA) as an illegal Schedule I drug which has no currently accepted medical use. However, on March 17, 1999, 11 independent scientists appointed by the Institute of Medicine reported that medical marijuana was effective in controlling some forms of pain, alleviating nausea and vomiting due to chemotherapy, treating wasting due to AIDS, and combating muscle spasms associated with multiple sclerosis. There was also no evidence that using marijuana would increase illicit drug use or that it was a "gateway" drug. Despite this evidence the DEA refuses to reclassify marijuana as a Schedule II drug, which would allow physicians to prescribe unadulterated and standardized forms of marijuana. After reviewing the pertinent scientific data and applying the principle of double effect, there is a proportionate reason for allowing physicians to prescribe marijuana. Seriously ill patients have the right to effective therapies. To deny patients access to such a therapy is to deny them dignity and respect as persons. PMID:10754797

Clark, P A

2000-01-01

442

The effectiveness of gateway communications in anti-marijuana campaigns.  

PubMed

Successful anti-marijuana messages can be hypothesized to have two types of effects, namely persuasion effects, that is, a change in people's beliefs about using marijuana, and priming effects, that is, a strengthened correlation between beliefs and associated variables such as attitude and intention. This study examined different sets of anti-drug advertisements for persuasion and priming effects. The ads targeted the belief that marijuana is a gateway to stronger drugs, a belief that is often endorsed by campaign planning officials and health educators. A sample of 418 middle and high school students was randomly assigned to a control video or one of three series of ads, two of which included the gateway message in either an explicit or implicit way. Results did not support the use of the gateway belief in anti-marijuana interventions. Whereas no clear persuasion or priming effects were found for any of the ad sequences, there is some possibility that an explicit gateway argument may actually boomerang. In comparison to the control condition, adolescents in the explicit gateway condition tended to agree less with the gateway message and displayed weaker correlations between anti-marijuana beliefs and their attitude toward marijuana use. The results suggest that the gateway message should not be used in anti-drug interventions. PMID:12746037

Yzer, Marco C; Cappella, Joseph N; Fishbein, Martin; Hornik, Robert; Ahern, R Kirkland

2003-01-01

443

Jordanian Adolescent Cannabis Use: Patterns, Risks, And Protective Factors  

Microsoft Academic Search

\\u000aJORDANIAN ADOLESCENT CANNABIS USE:\\u000aPATTERNS, RISKS, AND PROTECTIVE FACTORS\\u000aby\\u000aSUKAINA ALZYOUD\\u000aMonth, 2010\\u000aAdvisor: Dr. Stephanie Schim\\u000aMajor: Nursing\\u000aDegree: Doctor of Philosophy\\u000aBackground: Cannabis is considered to be the most commonly used substances worldwide. Its use is not only common among adolescents but is increasing in developing countries such as Jordan. Cannabis use among adolescents has been linked

Sukaina A. Alzyoud

2010-01-01

444

Vulnerability Factors for the Psychiatric and Behavioral Effects of Cannabis  

PubMed Central

Cogent evidence shows that cannabis plays a variable role on behavioral regulation and the pathophysiology of most psychiatric conditions. Accordingly, cannabis has been alternatively shown to exacerbate or ameliorate mental symptoms, depending on its composition and route of consumption, as well as specific individual and contextual characteristics. The vulnerability to the psychological effects of cannabis is influenced by a complex constellation of genetic and environmental factors. In the present article, we will review the current evidence on the pharmacological, individual and situational factors that have been documented to affect the behavioral and psychiatric effects of cannabinoids.

Bortolato, Marco; Bini, Valentina; Tambaro, Simone

2010-01-01

445

Effects of chronic, heavy cannabis use on executive functions.  

PubMed

This case describes the clinical course of a cannabis-dependent individual entering a 12-week abstinence-based research program. The case illustrates the effects of chronic, heavy cannabis use on executive functions at three time points: 1) 24 hours of abstinence; 2) 4 weeks of abstinence; and 3) 12 weeks of abstinence. It is followed by discussions by two clinical psychologists and a psychiatrist. The findings described here have important clinical implications, as executive functions have a vital role in treatment participation and in sustaining recovery. It should be of particular interest to clinicians who work with people with cannabis use disorders. PMID:21643485

Crean, Rebecca D; Tapert, Susan F; Minassian, Arpi; Macdonald, Kai; Crane, Natania A; Mason, Barbara J

2011-03-01

446

The Role of Study and Work in Cannabis Use and Dependence Trajectories among Young Adult Frequent Cannabis Users  

PubMed Central

Life course theory considers events in study and work as potential turning points in deviance, including illicit drug use. This qualitative study explores the role of occupational life in cannabis use and dependence in young adults. Two and three years after the initial structured interview, 47 at baseline frequent cannabis users were interviewed in-depth about the dynamics underlying changes in their cannabis use and dependence. Overall, cannabis use and dependence declined, including interviewees who quit using cannabis completely, in particular with students, both during their study and after they got employed. Life course theory appeared to be a useful framework to explore how and why occupational life is related to cannabis use and dependence over time. Our study showed that life events in this realm are rather common in young adults and can have a strong impact on cannabis use. While sometimes changes in use are temporary, turning points can evolve from changes in educational and employment situations; an effect that seems to be related to the consequences of these changes in terms of amount of leisure time and agency (i.e., feelings of being in control). PMID:23950748

Liebregts, Nienke; van der Pol, Peggy; Van Laar, Margriet; de Graaf, Ron; van den Brink, Wim; Korf, Dirk J.

2013-01-01

447

Evidence for Connections Between Prosecutor-Reported Marijuana Case Dispositions and Community Youth Marijuana-Related Attitudes and Behaviors  

Microsoft Academic Search

This article examines relationships between local drug policy (as represented by prosecutor-reported case outcomes for first-offender juvenile marijuana possession cases) and youth self-reported marijuana use, perceived risk, and disapproval. Interviews with prosecutors and surveys of 8th-, 10th-, and 12th-grade students in the United States were conducted in 2000. Analyses include data from 97 prosecutors and students from 127 schools in

Yvonne M. Terry-McElrath; Duane C. McBride; Jamie F. Chriqui; Patrick M. OMalley; Curtis J. VanderWaal; Frank J. Chaloupka; Lloyd D. Johnston

2009-01-01

448

The Motivational Enhancement Therapy and Cognitive Behavioral Therapy Supplement: 7 Sessions of Cognitive Behavioral Therapy for Adolescent Cannabis Users, Cannabis Youth Treatment (CYT) Series, Volume 2.  

ERIC Educational Resources Information Center

This manual, a supplement to "Motivational Enhancement Therapy and Cognitive Behavioral Therapy for Adolescent Cannabis Users: 5 Sessions, Cannabis Youth Treatment (CYT) Series, Volume 1", presents a seven-session cognitive behavioral treatment (CBT7) approach designed especially for adolescent cannabis users. It addresses the implementation and…

Webb, Charles; Scudder, Meleney; Kaminer, Yifrah; Kaden, Ron

449

Effects of cannabis use status on cognitive function, in males with schizophrenia.  

PubMed

Cognitive impairment and cannabis use are common among patients with schizophrenia. However, the moderating role of cannabis on cognition remains unclear. We sought to examine cognitive performance as a function of cannabis use patterns in schizophrenia. A secondary aim was to determine the effects of cumulative cannabis exposure on cognition. Cognition was assessed in male outpatients with current cannabis dependence (n=18) and no current cannabis use disorders (n=29). We then parsed non-current users into patients with lifetime cannabis dependence (n=21) and no lifetime cannabis dependence (n=8). Finally, as an exploratory analysis, we examined relationships between cumulative cannabis exposure and cognition in lifetime dependent patients. Cross-sectional comparisons suggest that lifetime cannabis users demonstrate better processing speed than patients with no lifetime dependence. Exploratory analyses indicated that patients with current dependence exhibited robust negative relationships between cumulative cannabis exposure and cognition; these associations were absent in former users. Cannabis status has minimal effects on cognition in males with schizophrenia. However, cumulative cannabis exposure significantly impairs cognition in current, but not former users, suggesting that the state dependent negative effects of cannabis may be reversed with sustained abstinence. Prospective studies are needed to confirm these findings. PMID:23246245

Rabin, Rachel A; Zakzanis, Konstantine K; Daskalakis, Zafiris J; George, Tony P

2013-04-30

450

Cannabis: a controversial 21st-century drug of antiquity.  

PubMed

Cannabis consumption has been popular for thousands of years and its historical use is noted in many parts of the world including ancient China, India, the Middle East. It is currently the most popular illicit drug in the world, is being utilized as a medicinal plant, and many parts of the world are legalizing this drug. This discussion considers various aspects of cannabis use including its prevalence, history, co-morbid drug abuse, designer cannabinoids, psychiatric adverse effects, medical adverse effects, and management options. The youth of the world should be comprehensively taught that cannabis is neither a safe nor a benign drug. Prevention with comprehensive drug education is the best plan for our youth since management of a chronic or heavy cannabis consummer remains difficult and fraught with failure if cessation is the goal. Caveat emptor! PMID:24940853

Greydanus, D; Holt, M

2014-05-01

451

[Perceptions of cannabis effects a qualitative study among adolescents].  

PubMed

The aim of the study was to compare perceptions of cannabis use effects and risks of tolerance effect, withdrawal syndrome, dependence and repercussions on school, social, and familial functioning among adolescent cannabis users and non users. Subjects were 210 adolescents (121 boys, 89 girls; mean age=16.3 1.3) from the department of Pyrénées-Orientales, France. Subjects completed a questionnaire assessing the frequency of cannabis use, the method of using cannabis, and including open-ended questions (What are the different methods of cannabis use? What are their pleasant and unpleasant or negative effects? What are their risks? Do you think that cannabis effects decrease in intensity when you are used to it? When someone is used to cannabis and stop using it (or has no more of it), does she experience craving for cannabis and withdrawal symptoms? What do you think of cannabis use?). Among the subjects, 118 (56.2%) were cannabis users and 92 (43.8%) were non-users. Among users, 27% used cannabis once a Month or less than once a Month, 21%, more than once a Month; 24%, more than once a weeks; 6%, every day; 20%, more than once a day. The methods of using cannabis were joints (76%), bong (40%), pipe (23%), and ingestion (18%). Knowledge of methods of using cannabis was higher in users than non-users: joint (87% vs 64%, p<0.0001), bong (69% vs 21%, p<0.0001), pipe (38% vs 7%, p<0.0001), ingestion (41% vs 13%, p<0.0001). Fifty-four per cent of users reported that cannabis use induces pleasant affects versus 30% of non-users (p=0.0006). They were exhilaration (47% vs 9%), relaxation (40% vs 23%), cheerfulness (21% vs 10%). Twenty-seven percent of users reported that cannabis use reduces negative feelings versus 14% of non-users (p=0.02). To be more open to social relationships was mentioned by 13% of users versus 1% of non-users (p=0.0001). The negative effects that were reported were attention and cognitive impairment (13% of users vs 5% of non users, p=0.05), irritability (8% vs 8%), loss of control (8% vs 8%) and feeling faint (13% vs 6%, p=0.09). Users reported than bong has much quicker and stronger effects than joints. The effects of bong class cannabis as a hard drug. Physical negative effects or risk were reported by 35% of users versus 30% of non-users (p=0.44). Bong users described specific physical risks such as respiratory problems and fainting. No subjects reported the risk of road accidents. Most users and non-users considered that cannabis use causes dependence (60% vs 74%, p=0.03), tolerance (68% vs 60%, p=0.23), and withdrawal symptoms (76% vs 52%, p<0.001). A minority of users and non-users reported that cannabis use causes a deterioration in school functioning (42% vs 20%, p=0.69), in social activities (23% vs 14%, p=0.10) and in family relationships (29% vs 20%, p=0.14). Most of users (56%) had a global positive opinion of cannabis use whereas most non-users (66%) had a global negative opinion of cannabis use. The frequency and methods of use reported in this study compare with the results of a recent study carried out in another town of the south of France. These results suggest that a high proportion of French adolescents are using cannabis and that a high proportion of users utilize bongs. Perception of cannabis effects and risks of tolerance effect, withdrawal syndrome, dependence and repercussions on school, social, and familial functioning differed between users and non-users. Users have more positive beliefs and less negative beliefs about cannabis than non-users. Users reported more frequently pleasant effects and less frequently unpleasant or negative effects, physical risks, risks of dependence, deterioration in school, social, and familial functioning than non-users. However, only a minority of non-users reported negative effects or consequences of cannabis use. None subjects reported a risk of road accident. These results suggest that information on negative effects, risks and repercussions of cannabis use may be a target for prevention intervention. PMID:15235524

Chabrol, H; Roura, C; Kallmeyer, A

2004-01-01

452

Socialization instances linked to cannabis experimentation among French teenagers.  

PubMed

France presents one of the highest prevalence of teenagers aged 15-year-olds who report they already have experienced cannabis in Europe. Data from the French 2010 Health Behavior in School-aged Children (HSBC) survey and environmental parameters typifying schools 'neighborhoods were used to study cannabis experimentation. We conducted a two-level logistic regression (clusters being schools) on 4,175 French 8th-10th graders from 156 schools. Several individual parameters were linked to cannabis experimentation. Living in a non-intact family, feeling insufficiently monitored, having poor communication with mother and being from a family with a high socio-economic status (SES) were all associated with increased risk of cannabis experimentation. At environmental level, only being in a priority education area was linked to this behavior, without explaining differences among schools. PMID:25099311

Jovic, Sonia; Genolini, Christophe; Delpierre, Cyrille; Spilka, Stanislas; Ehlinger, Virginie; Ross, Jim; Arnaud, Catherine; Godeau, Emmanuelle

2014-11-01

453

Cannabis and cognitive dysfunction: Parallels with endophenotypes of schizophrenia?  

PubMed Central

Currently, there is a lot of interest in cannabis use as a risk factor for the development of schizophrenia.